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All publications of Theoretical Physics
Our 200 latest journal publications.
Our 200 latest journal publications. A complete list is available in the DiVA system.
PID,Name,Title,PublicationType,ContentType,Language,Journal,JournalISSN,JournalEISSN,Status,Volume,Issue,HostPublication,StartPage,EndPage,Year,Edition,Pages,City,Publisher,Series,SeriesISSN,SeriesEISSN,ISBN,Urls,ISRN,DOI,ISI,PMID,ScopusId,NBN,LocalId,ArchiveNumber,Keywords,Categories,ResearchSubjects,Projects,Notes,Abstract,Opponents,Supervisors,Examiners,Patent,ThesisLevel,Credits,Programme,Subject,Uppsok,DefencePlace,DefenceLanguage,DefenceDate,CreatedDate,PublicationDate,LastUpdated,FullTextLink,Funder,NumberOfAuthors,ExternalCooperation,FridaLevel,PartOfThesis,PublicationSubtype,Conference,Term,ArticleId,Reviewed,FreeFulltext,SustainableDevelopment,Contributor
"1515606","Ektarawong, A. (Chulalongkorn Univ, Thailand; Thailand Ctr Excellence Phys, Thailand);Tsuppayakorn-aek, P. (Chulalongkorn Univ, Thailand; Thailand Ctr Excellence Phys, Thailand);Bovornratanaraks, T. (Chulalongkorn Univ, Thailand; Thailand Ctr Excellence Phys, Thailand);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Kanchanavatee, N. (Chulalongkorn Univ, Thailand; Thailand Ctr Excellence Phys, Thailand)","Effect of thermally excited lattice vibrations on the thermodynamic stability of tungsten ditellurides WTe2 under high pressure: A first-principles investigation","Artikel i tidskrift","Refereegranskat","eng","Computational materials science","0927-0256","1879-0801","published","186","","","","","2021","","","","ELSEVIER","","","","","","","10.1016/j.commatsci.2020.110024","000594495400003","","","urn:nbn:se:liu:diva-172403","","","First-principles calculations; Density functional theory; Thermodynamic stability; Tungsten ditellurides WTe2; Lattice vibrations","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Thailand Toray Science Foundation (TTSF); Ratchadaphiseksomphot Endowment Fund, Chulalongkorn UniversityChulalongkorn University [CU-GR_62_66_23_26]; Ratchadaphiseksomphot Endowment Fund, Chulalongkorn UniversityChulalongkorn University; Grants for Development of New Faculty Staff and the Research Fund for DPST Graduate [003/2015]; Institute for the Promotion of Teaching Science and Technology (IPST), Thailand; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; Swedish Foundation [FFL 15-0290]; Swedish Research Council (VR)Swedish Research Council [2019-05403]; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation [KAW-2018.0194]</p>","<p>The thermodynamic stability as a function of pressure and temperature of three WTe2 polytypes, i. e., Td, 1T , and 2H phases, is examined using first-principles calculations, where the temperature-dependent contributions, arising particularly from the lattice vibrations, are derived from the quasiharmonic approximation. We find that the critical transition pressure to the 2H phase increases almost linearly with increasing temperature. Through the inspection of the phonon density of states, 2H-WTe2 is dynamically stable not only at high pressure, but also at zero pressure, indicating possible existence of 2H-WTe2 also at ambient conditions. On the other side, our results demonstrate that, at relevant temperature and pressure, the thermodynamic stability of 1T-WTe2 is comparable to that of Td-WTe2, and further analysis reveals substantial similarities in terms of structural behavior between Td-WTe2 and 1T-WTe2. These findings suggest not only that the two polytypes are likely to coexist in practical samples of WTe2 due probably to grains/regions either with tiny difference in stress, for example, or with different growth history, but also that the designation of 1T , having been regularly used to described the compound under pressure in the literature, might actually be a mixture of Td and 1T polytypes, whose WTe2 layers laterally slide via low transition barrier induced probably by the applied pressure, resulting in the splitting of (101) and (113) peaks as observed in the diffraction experiments.</p>","","","","","","","","","","","","","2021-01-10","2021-01-10","2021-01-28","","","5","","2","","","","","110024","false","","",""
"1527422","Kakanakova-Gueorguieva, Anelia [aneka59] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ivanov, Ivan Gueorguiev [ivaiv28] [0000-0003-1000-0437] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Suwannaharn, Nattamon [natsu01] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Chulalongkorn Univ, Thailand);Chih-Wei, Chih-Wei [chihs22] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Cora, Ildiko (Inst Tech Phys & Mat Sci, Hungary);Pecz, Bela (Inst Tech Phys & Mat Sci, Hungary);Giannazzo, Filippo (CNR, Italy);Sangiovanni, Davide [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Gueorguiev, Gueorgui Kostov [guegu96] [0000-0001-9402-1491] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902])","MOCVD of AlN on epitaxial graphene at extreme temperatures","Artikel i tidskrift","Refereegranskat","eng","CrystEngComm","1466-8033","1466-8033","published","23","2","","385","390","2021","","","","ROYAL SOC CHEMISTRY","","","","","","","10.1039/d0ce01426e","000608614100016","","","urn:nbn:se:liu:diva-173178","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|FLAG-ERA 2015 JTC project GRIFONE through the Swedish Research Council [VR2015-06816]; National Research Development and Innovation Office, Hungary [NN 118914]; Swedish Research CouncilSwedish Research Council [SNIC 2020/5-146, SNIC 2020/14-17, VR2018-05973]; Olle Engkvist Foundation; [VR2017-04071]; [AF15-557]; [AF18-266]; [VR2016-05362]</p>","<p>The initial stages of metal organic chemical vapor deposition (MOCVD) of AlN on epitaxial graphene at temperatures in excess of 1200 degrees C have been rationalized. The use of epitaxial graphene, in conjunction with high deposition temperatures, can deliver on the realization of nanometer thin AlN whose material quality is characterized by the appearance of luminescent centers with narrow spectral emission at room temperature. It has been elaborated, based on our previous comprehensive ab initio molecular dynamics simulations, that the impact of graphene on AlN growth consists in the way it promotes dissociation of the trimethylaluminum, (CH3)(3)Al, precursor with subsequent formation of Al adatoms during the initial stages of the deposition process. The high deposition temperatures ensure adequate surface diffusion of the Al adatoms which is an essential factor in material quality enhancement. The role of graphene in intervening with the dissociation of another precursor, trimethylgallium, (CH3)(3)Ga, has accordingly been speculated by presenting a case of propagation of ultrathin GaN of semiconductor quality. A lower deposition temperature of 1100 degrees C in this case has better preserved the structural integrity of epitaxial graphene. Breakage and decomposition of the graphene layers has been deduced in the case of AlN deposition at temperatures in excess of 1200 degrees C.</p>","","","","","","","","","","","","","2021-02-10","2021-02-10","2021-03-02","http://liu.diva-portal.org/smash/get/diva2:1527422/FULLTEXT01.pdf","","9","","1","","","","","","false","","",""
"1529955","Gharavi, Mohammad Amin [mohgh20] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Le Febvrier, Arnaud [arnle40] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Lu, Jun [junlu07] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Greczynski, Grzegorz [grzgr49] [0000-0002-4898-5115] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Armiento, Rickard [ricar47] [0000-0002-5571-0814] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Eklund, Per [perek02] [0000-0003-1785-0864] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Phase Transformation and Superstructure Formation in (Ti-0.5, Mg-0.5)N Thin Films through High-Temperature Annealing","Artikel i tidskrift","Refereegranskat","eng","Coatings","2079-6412","","published","11","1","","","","2021","","","","MDPI","","","","","","","10.3390/coatings11010089","000610009300001","","","urn:nbn:se:liu:diva-173427","","","sputtering; thermoelectrics; titanium nitride; magnesium nitride; ternary nitride","Materialkemi (10403)","","","<p>Funding Agencies|Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; Knut and Alice Wallenberg foundationKnut & Alice Wallenberg Foundation [KAW-2020.0196, KAW-2018.0194]; Swedish Research Council (VR)Swedish Research Council [2016-03365, 2019-05403]; Swedish Foundation for Strategic ResearchSwedish Foundation for Strategic Research [FFL 15-0290]; Swedish Research CouncilSwedish Research Council [2018-05973]</p>","<p>(Ti-0.5, Mg-0.5)N thin films were synthesized by reactive dc magnetron sputtering from elemental targets onto c-cut sapphire substrates. Characterization by theta-2 theta X-ray diffraction and pole figure measurements shows a rock-salt cubic structure with (111)-oriented growth and a twin-domain structure. The films exhibit an electrical resistivity of 150 m omega center dot cm, as measured by four-point-probe, and a Seebeck coefficient of -25 mu V/K. It is shown that high temperature (similar to 800 degrees C) annealing in a nitrogen atmosphere leads to the formation of a cubic LiTiO2-type superstructure as seen by high-resolution scanning transmission electron microscopy. The corresponding phase formation is possibly influenced by oxygen contamination present in the as-deposited films resulting in a cubic superstructure. Density functional theory calculations utilizing the generalized gradient approximation (GGA) functionals show that the LiTiO2-type TiMgN2 structure has a 0.07 eV direct bandgap.</p>","","","","","","","","","","","","","2021-02-20","2021-02-20","2021-03-10","http://liu.diva-portal.org/smash/get/diva2:1529955/FULLTEXT01.pdf","","7","","0","","","","","89","false","","",""
"1529987","Ivády, Viktor [vikiv58] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Wigner Res Ctr Phys, Hungary);Zheng, Huijie (Johannes Gutenberg Univ Mainz, Germany; GSI Helmholtzzentrum Schwerionenforsch, Germany);Wickenbrock, Arne (Johannes Gutenberg Univ Mainz, Germany; GSI Helmholtzzentrum Schwerionenforsch, Germany);Bougas, Lykourgos (Johannes Gutenberg Univ Mainz, Germany);Chatzidrosos, Georgios (Johannes Gutenberg Univ Mainz, Germany);Nakamura, Kazuo (Tokyo Gas Co Ltd, Japan);Sumiya, Hitoshi (Sumitomo Elect Ind Ltd, Japan);Ohshima, Takeshi (Natl Inst Quantum & Radiol Sci & Technol, Japan);Isoya, Junichi (Univ Tsukuba, Japan);Budker, Dmitry (Johannes Gutenberg Univ Mainz, Germany; GSI Helmholtzzentrum Schwerionenforsch, Germany; Univ Calif Berkeley, CA 94720 USA);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Gali, Adam (Wigner Res Ctr Phys, Hungary; Budapest Univ Technol & Econ, Hungary)","Photoluminescence at the ground-state level anticrossing of the nitrogen-vacancy center in diamond: A comprehensive study","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","103","3","","","","2021","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.103.035307","000609013000003","","","urn:nbn:se:liu:diva-173402","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|MTA Premium Postdoctoral Research Program; Knut and Alice Wallenberg Foundation through WBSQD2 project [2018.0071]; National Research, Development and Innovation Office of Hungary (NKFIH) of the National Excellence Program of Quantum-coherent materials project [KKP129866]; National Research, Development and Innovation Office of Hungary (NKFIH) of the EU QuantERA program Q magine [NN127889]; NKFIH through the National Quantum Technology Program [2017-1.2.1-NKP-2017-00001]; Quantum Information National Laboratory - Ministry of Innovation and Technology of Hungary; EU FETOPEN Flagship Project ASTERIQ [820394]; German Federal Ministry of Education and Research (BMBF)Federal Ministry of Education & Research (BMBF) [FKZ 13N14439, FKZ 13N15064]; Cluster of Excellence Precision Physics, Fundamental Interactions, and Structure of Matter - German Research Foundation (DFG) within the German Excellence StrategyGerman Research Foundation (DFG) [PRISMA+ EXC 2118/1, 39083149]</p>","<p>The nitrogen-vacancy center (NV center) in diamond at magnetic fields corresponding to the ground-state level anticrossing (GSLAC) region gives rise to rich photoluminescence (PL) signals due to the vanishing energy gap between the electron spin states, which enables for a broad variety of environmental couplings to have an effect on the NV centers luminescence. Previous works have addressed several aspects of the GSLAC photoluminescence, however, a comprehensive analysis of the GSLAC signature of NV ensembles in different spin environments at various external fields is missing. Here we employ a combination of experiments and recently developed numerical methods to investigate in detail the effects of transverse electric and magnetic fields, strain, P1 centers, NV centers, and the C-13 nuclear spins on the GSLAC photoluminescence. Our comprehensive analysis provides a solid ground for advancing various microwave-free applications at the GSLAC, including but not limited to magnetometry, spectroscopy, dynamic nuclear polarization (DNP), and nuclear magnetic resonance (NMR) detection. We demonstrate that not only the most abundant (NV)-N-14 center but the (NV)-N-15 can also be utilized in such applications.</p>","","","","","","","","","","","","","2021-02-20","2021-02-20","2021-03-10","http://liu.diva-portal.org/smash/get/diva2:1529987/FULLTEXT01.pdf","","12","","2","","","","","035307","false","","",""
"1527423","Mikula, Marian (Comenius Univ, Slovakia; SAS, Slovakia);Uzon, Stela (Comenius Univ, Slovakia);Hudec, Tomas (Univ Southampton, England);Grancic, Branislav (Comenius Univ, Slovakia);Truchly, Martin (Comenius Univ, Slovakia);Roch, Tomas (Comenius Univ, Slovakia);Svec, Peter Jr. (Slovak Acad Sci, Slovakia);Satrapinskyy, Leonid (Comenius Univ, Slovakia);Caplovicova, Maria (Slovak Univ Technol Bratislava, Slovakia);Greczynski, Grzegorz [grzgr49] [0000-0002-4898-5115] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Petrov, Ivan [ivape26] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Illinois, IL 61801 USA; Natl Taiwan Univ Sci & Technol, Taiwan);Odén, Magnus [magod41] [0000-0002-2286-5588] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Nanostrukturerade material [2221]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Kus, Peter (Comenius Univ, Slovakia);Sangiovanni, Davide [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Thermally induced structural evolution and age-hardening of polycrystalline V1-xMoxN (x approximate to 0.4) thin films","Artikel i tidskrift","Refereegranskat","eng","Surface & Coatings Technology","0257-8972","1879-3347","published","405","","","","","2021","","","","ELSEVIER SCIENCE SA","","","","","","","10.1016/j.surfcoat.2020.126723","000604583200111","","","urn:nbn:se:liu:diva-173177","","","(V;Mo)N; Sputtering; Decomposition; Hardening; Ab initio molecular dynamics","Oorganisk kemi (10404)","","","<p>Funding Agencies|Slovak Research and Development AgencySlovak Research and Development Agency [APVV-17-0320]; Scientific Grant Agency [VEGA 1/0381/19]; Operational Program Research and Development [ITMS 26210120010]; Swedish Research CouncilSwedish Research Council [2016-07213]; VINN Excellence Center Functional Nanoscale Materials (FunMat-2) [2016-05156]; Olle Engkvist Foundation; Swedish Government Strategic Research Area in Materials Science on Advanced Functional Materials at Linkoping University (Faculty Grant SFO-MatLiU) [2009-00971]</p>","<p>Rocksalt-structure (B1) (V,Mo)N alloys are inherently hard and tough ceramics. However, the mechanical properties and thermal stability of (V,Mo)N solid solutions at temperatures greater than or similar to 700 degrees C of relevance for practical applications have not been previously investigated. In this work, we synthesize single-phase B1 polycrystalline V0.57Mo0.43N0.95 coatings to investigate the effects induced by temperature on the nanostructural evolution and hardness (H) of the material. Nanoindentation measurements show that the as-deposited film (H = 23 +/- 3 GPa) becomes approximate to 30% harder (up to 31 +/- 2 GPa) upon annealing at 730 C. Experimental characterization and analyses, based on dispersive X-ray spectroscopy, X-ray diffraction (XRD), and transmission electron microscopy (TEM), reveal that the age-hardening effect originates from decomposition of the solid solution into coherent strained cubic VN-rich/MoN-rich domains. The experimental results are complemented by the composition/temperature (V,Mo)N phase diagram - constructed upon ab initio molecular dynamics free-energies - which indicates that the separation observed in the solid solutions is of spinodal nature. Films annealed at temperatures exceeding 850 degrees C undergo structural coarsening, with formation of hexagonal MoxNy and cubic VN phases, which cause a decrease in hardness to approximate to 22 GPa. Our present findings indicate that (V,Mo)N coatings may offer outstanding mechanical performances during operation at elevated temperatures.</p>","","","","","","","","","","","","","2021-02-10","2021-02-10","2021-03-10","","","14","","1","","","","","126723","false","","",""
"1538742","Barcza, Gergely (Wigner Res Ctr Phys, Hungary; Czech Acad Sci, Czech Republic);Ivády, Viktor [vikiv58] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Wigner Res Ctr Phys, Hungary);Szilvasi, Tibor (Univ Wisconsin, WI 53706 USA; Univ Alabama, AL 35487 USA);Voros, Marton (Argonne Natl Lab, IL 60439 USA);Veis, Libor (Czech Acad Sci, Czech Republic);Gali, Adam (Wigner Res Ctr Phys, Hungary; Budapest Univ Technol & Econ, Hungary);Legeza, Ors (Wigner Res Ctr Phys, Hungary)","DMRG on Top of Plane-Wave Kohn-Sham Orbitals: A Case Study of Defected Boron Nitride","Artikel i tidskrift","Refereegranskat","eng","Journal of Chemical Theory and Computation","1549-9618","1549-9626","published","17","2","","1143","1154","2021","","","","AMER CHEMICAL SOC","","","","","","","10.1021/acs.jctc.0c00809","000618869600043","33435672","","urn:nbn:se:liu:diva-174389","","","","Teoretisk kemi (10407)","","","<p>Funding Agencies|NKFIH [PD-17-125261, FK-20-135496, K120569, K134983]; Bolyai Research Scholarship of the Hungarian Academy of SciencesHungarian Academy of Sciences; MTA Premium Postdoctoral Research Program; Knut and Alice Wallenberg Foundation through WBSQD2 project [2018.0071]; Czech Science FoundationGrant Agency of the Czech Republic [18-18940Y]; NKFIH through the National Quantum Technology Program [2017-1.2.1-NKP-2017-00001]; Alexander von Humboldt FoundationAlexander von Humboldt Foundation; Hungarian NKFIH of the National Excellence Program of the Quantum-coherent materials project [KKP129866]; Center for Scalable and Predictive methods for Excitation and Correlated phenomena (SPEC) from the Computational Chemical Sciences Program by the U.S. Department of Energy (DOE), at the Pacific Northwest National LaboratoryUnited States Department of Energy (DOE)</p>","<p>In this paper, we analyze the numerical aspects of the inherent multireference density matrix renormalization group (DMRG) calculations on top of the periodic Kohn-Sham density functional theory using the complete active space approach. The potential of the framework is illustrated by studying hexagonal boron nitride nanoflakes embedding a charged single boron vacancy point defect by revealing a vertical energy spectrum with a prominent multireference character. We investigate the consistency of the DMRG energy spectrum from the perspective of sample size, basis size, and active space selection protocol. Results obtained from standard quantum chemical atom-centered basis calculations and plane-wave based counterparts show excellent agreement. Furthermore, we also discuss the spectrum of the periodic sheet which is in good agreement with extrapolated data of finite clusters. These results pave the way toward applying the DMRG method in extended correlated solid-state systems, such as point defect qubit in wide band gap semiconductors.</p>","","","","","","","","","","","","","2021-03-21","2021-03-21","2021-03-21","","","7","","1","","","","","","false","","",""
"1541704","Dinsdale, Alan (Hampton Thermodynam Ltd, England);Khvan, Alexandra (NUST MISiS, Russia);Smirnova, Ekaterina A. (NUST MISiS, Russia);Ponomareva, Alena V. (NUST MISiS, Russia);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (NUST MISiS, Russia)","Modelling the thermodynamic data for hcp Zn and Cu -Zn alloys-an ab initio and calphad approach","Artikel i tidskrift","Refereegranskat","eng","Calphad","0364-5916","1873-2984","published","72","","","","","2021","","","","PERGAMON-ELSEVIER SCIENCE LTD","","","","","","","10.1016/j.calphad.2021.102253","000623906800001","","","urn:nbn:se:liu:diva-174780","","","Zn; Cd; Thermodynamic data; hcp; Cu-Zn; ab initio","Metallurgi och metalliska material (20506)","","","<p>Funding Agencies|Ministry of Education and Science of the Russian Federation of NUST ""MISiS"" [K2-2019-003]; Russian Science FoundationRussian Science Foundation (RSF) [18-12-00492]; Knut and Alice Wallenberg Foundation (Wallenberg Scholar Grant) [KAW-2018.0194]</p>","<p>The phase diagrams of systems between zinc and elements such as Cu, Ag and Au show two distinct hcp phases on the Zn side of the system. Because of this, it is difficult to model the thermodynamic properties of these phases within a single dataset. As a result it is common to assess the data for these systems with two hexagonal phases, a phase HCP_A3 with a near ideal c/a ratio and the terminal solid solution of Zn with an anomalously high value for this ratio designated as HCP_ZN. We have examined the effect of additions of Cu on the enthalpy of mixing and lattice parameters of HCP_ZN in order to verify, using ab initio calculations, the origin of the above mentioned thermodynamic model for the alloy. The analysis of the calculations allows us to suggest a possible alternative to the state-of-the-art two hcp phases approach akin to the magnetic model used with success within the CALPHAD modelling.</p>","","","","","","","","","","","","","2021-04-01","2021-04-01","2021-04-01","","","5","","1","","","","","102253","false","","",""
"1535967","Ektarawong, A. (Chulalongkorn Univ, Thailand; Minist Higher Educ Sci Res & Innovat, Thailand; Chulalongkorn Univ, Thailand);Khamkaeo, S. (Chulalongkorn Univ, Thailand; Minist Higher Educ Sci Res & Innovat, Thailand);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Bovornratanaraks, T. (Chulalongkorn Univ, Thailand; Minist Higher Educ Sci Res & Innovat, Thailand)","A comparison of the mixing thermodynamics of the antifluorite-structured Mg2Si1-xGex, Mg2Sn1-xGex and Mg2Si1-xSnx alloys from first principles","Artikel i tidskrift","Refereegranskat","eng","Vacuum","0042-207X","1879-2715","published","185","","","","","2021","","","","PERGAMON-ELSEVIER SCIENCE LTD","","","","","","","10.1016/j.vacuum.2020.110018","000618236700002","","","urn:nbn:se:liu:diva-173856","","","First-principles calculations; Density functional theory; Cluster expansion; Magnesium compounds/alloys; Thermodynamic stability","Oorganisk kemi (10404)","","","<p>Funding Agencies|Thailand Toray Science Foundation (TTSF); Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University, Faculty Grant SFOMatLiU [2009 00971]; Swedish Foundation for Strategic Research through the Future Research Leaders 6 program [FFL 15-0290]; Swedish Research Council (VR)Swedish Research Council [2019-05403]; Knut and Alice Wallenberg Foundation, Sweden (Wallenberg Scholar Grant) [KAW-2018.0194]</p>","<p>The mixing thermodynamics of the antifluorite-structured Mg2Si1-xGex is investigated using the first-principles calculations. We find that Mg2Si and Mg2Ge readily mix with each other leading to formation of a single-phase random solid solutions of Mg2Si1-xGex across the entire composition range from the temperature of about 50 K and above. At 0 K, Mg2Si1-xGex exhibits a weak energy preference toward local phase segregation into Mg2Si and Mg2Ge without forming any ordered patterns of Si and Ge atoms. Through a comparison with the mixing thermodynamics of Mg2Sn with Mg2Si or Mg2Ge, a small lattice misfit between Mg2Si and Mg2Ge of less than 1 % is responsible for the formation of stable Mg2Si1-xGex random solid solutions at such a low temperature. Besides their thermodynamic stability, our prediction reveals that the random solid solutions of Mg2Si1-xGex are dynamically and mechanically stable. These findings justify the uses of structural models of Mg2Si1-xGex, assuming a random distribution of Si and Ge atoms in the previous theoretical studies, and also provide an insight into the complete solubility of Mg2Ge in Mg2Si and vice versa at all temperature where the atomic diffusion is activated.</p>","","","","","","","","","","","","","2021-03-09","2021-03-09","2021-04-07","","","4","","1","","","","","110018","false","","",""
"1537506","Bykov, Maxim (Howard Univ, DC 20059 USA; Carnegie Inst Sci, DC 20015 USA);Bykova, Elena (Carnegie Inst Sci, DC 20015 USA);Ponomareva, Alena V. (Natl Univ Sci & Technol MISIS, Russia);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Chariton, Stella (Univ Chicago, IL 60437 USA);Prakapenka, Vitali B. (Univ Chicago, IL 60437 USA);Mahmood, Mohammad F. (Howard Univ, DC 20059 USA);Dubrovinsky, Leonid (Bayer Geoinst, Germany);Goncharov, Alexander F. (Carnegie Inst Sci, DC 20015 USA)","Stabilization of Polynitrogen Anions in Tantalum-Nitrogen Compounds at High Pressure","Artikel i tidskrift","Refereegranskat","eng","Angewandte Chemie International Edition","1433-7851","1521-3773","aheadofprint","","","","","","2021","","","","WILEY-V C H VERLAG GMBH","","","","","","","10.1002/anie.202100283","000627043600001","33556216","","urn:nbn:se:liu:diva-174185","","","high-energy-density materials; high pressure; nitrides; polynitrides; tantalum nitride","Organisk kemi (10405)","","","<p>Funding Agencies|Ministry of Science and Higher Education of the Russian Federation [K2-2020-026]; SFO in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [200900971]; DOE Office of ScienceUnited States Department of Energy (DOE) [DE-AC02-06CH11357]; National Science Foundation - Earth SciencesNational Science Foundation (NSF) [EAR-1634415]; Department of Energy, GeosciencesUnited States Department of Energy (DOE) [DE-FG02-94ER14466]</p>","<p>The synthesis of polynitrogen compounds is of great importance due to their potential as high-energy-density materials (HEDM), but because of the intrinsic instability of these compounds, their synthesis and stabilization is a fundamental challenge. Polymeric nitrogen units which may be stabilized in compounds with metals at high pressure are now restricted to non-branched chains with an average N-N bond order of 1.25, limiting their HEDM performances. Herein, we demonstrate the synthesis of a novel polynitrogen compound TaN5 via a direct reaction between tantalum and nitrogen in a diamond anvil cell at circa 100 GPa. TaN5 is the first example of a material containing branched all-single-bonded nitrogen chains [N-5(5-)](infinity). Apart from that we discover two novel Ta-N compounds: TaN4 with finite N-4(4-) chains and the incommensurately modulated compound TaN2-x, which is recoverable at ambient conditions.</p>","","","","","","","","","","","","","2021-03-15","2021-03-15","2021-04-08","","","9","","2","","","","","","false","","",""
"1537232","Laniel, Dominique (Univ Bayreuth, Germany);Binck, Jannes (Goethe Univ, Germany);Winkler, Bjoern (Goethe Univ, Germany);Vogel, Sebastian (Univ Munich LMU, Germany);Fedotenko, Timofey (Univ Bayreuth, Germany);Chariton, Stella (Univ Chicago, IL 60637 USA);Prakapenka, Vitali (Univ Chicago, IL 60637 USA);Milman, Victor (BIOVIA Dassault Syst, England);Schnick, Wolfgang (Univ Munich LMU, Germany);Dubrovinsky, Leonid (Univ Bayreuth, Germany);Doubrovinckaia, Natalia [natdo06] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Bayreuth, Germany)","Synthesis, crystal structure and structure-property relations of strontium orthocarbonate, Sr2CO4","Artikel i tidskrift","Refereegranskat","eng","Acta Crystallographica. Section B: Structural Science, Crystal Engineering and Materials","2052-5192","2052-5206","published","77","","","131","137","2021","","","","International Union of Crystallography","","","","","","","10.1107/S2052520620016650","000618681800013","","","urn:nbn:se:liu:diva-174143","","","orthocarbonates; crystal structure; single-crystal X-ray diffraction; high pressure; Sr2CO4","Oorganisk kemi (10404)","","","<p>Funding Agencies|Alexander von Humboldt-StiftungAlexander von Humboldt Foundation; Bundesministerium fur Bildung und ForschungFederal Ministry of Education & Research (BMBF) [05K19WC1]; Deutsche ForschungsgemeinschaftGerman Research Foundation (DFG) [DU 954-11/1, DU 393-9/2, DU 393-13/1, FOR2125, WI1232]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]</p>","<p>Carbonates containing CO4 groups as building blocks have recently been discovered. A new orthocarbonate, Sr2CO4 is synthesized at 92 GPa and at a temperature of 2500 K. Its crystal structure was determined by in situ synchrotron single-crystal X-ray diffraction, selecting a grain from a polycrystalline sample. Strontium orthocarbonate crystallizes in the orthorhombic crystal system (space group Pnma) with CO4, SrO9 and SrO11 polyhedra as the main building blocks. It is isostructural to Ca2CO4. DFT calculations reproduce the experimental findings very well and have, therefore, been used to predict the equation of state, Raman and IR spectra, and to assist in the discussion of bonding in this compound.</p>","","","","","","","","","","","","","2021-03-15","2021-03-15","2021-04-13","http://liu.diva-portal.org/smash/get/diva2:1537232/FULLTEXT01.pdf","","11","","1","","","","","","false","","",""
"1543867","Baldinozzi, Gianguido (Univ Paris Saclay, France);Casillas Trujillo, Luis [luica08] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Patel, Maulik K. (Univ Liverpool, England);Sickafus, Kurt E. (Univ Tennessee, TN 37996 USA)","Structural complexity of Y6BO12 fluorite-related ternary oxides","Artikel i tidskrift","Refereegranskat","eng","MRS ADVANCES","2059-8521","","aheadofprint","","","","","","2021","","","","SPRINGER HEIDELBERG","","","","","","","10.1557/s43580-021-00038-9","000625624600001","","","urn:nbn:se:liu:diva-174969","","","","Oorganisk kemi (10404)","","","","<p>Oxides with generic stoichiometry M7O12 occupy, in a generic phase diagram, an intermediate place between fluorite and bixbyite structure types. Their structure is derived from the ideal fluorite structure, and it is characterized by a more or less pronounced ordering of the O vacancies within the average fluorite sublattice. We believe that ternary oxides with this kind of formula provide interesting degrees of flexibility for understanding the structural characteristic of these structures in the context of fission product stabilization in nuclear fuels and in the field of actinide waste forms as well. We would like to discuss the structural characteristics of the chemical bonds in ternary systems consisting of trivalent and hexavalent cations. Eventually, in compounds with generic formula Y6B+6O12, the B cation can be either a transition metal (W, Mo) or hexavalent uranium. We believe that studying the polyhedron of the sevenfold coordinated Y ion is particularly interesting to understand the flexibility of the chemical bonds: it is often described in the literature as a mono-capped trigonal prism, with bond lengths exhibiting an extremely large dispersion, ranging for instance from 2.19 to 2.70 angstrom in Y6WO12. We would discuss the implications of this large dispersion of distances on the chemical bond characteristics and compare DFT models with established experimental knowledge on pristine and irradiated specimens. Graphic abstract</p>","","","","","","","","","","","","","2021-04-13","2021-04-13","2021-04-13","","","4","","0","","","","","","true","","",""
"1538777","Pakhomova, Anna (Deutsch Elektronen Synchrotron DESY, Germany);Fuchs, Birgit (Univ Innsbruck, Austria);Dubrovinsky, Leonid S. (Univ Bayreuth, Germany);Doubrovinckaia, Natalia [natdo06] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Bayreuth, Germany);Huppertz, Hubert (Univ Innsbruck, Austria)","Polymorphs of the Gadolinite-Type Borates ZrB2O5 and HfB2O5 Under Extreme Pressure","Artikel i tidskrift","Refereegranskat","eng","Chemistry - A European Journal","0947-6539","1521-3765","aheadofprint","","","","","","2021","","","","WILEY-V C H VERLAG GMBH","","","","","","","10.1002/chem.202005244","000624614500001","33544397","","urn:nbn:se:liu:diva-174465","","","borates; diamond anvil cell; gadolinite structure; high-pressure chemistry; synchrotron radiation","Oorganisk kemi (10404)","","","<p>Funding Agencies|Federal Ministry of Education and Research, Germany (BMBF)Federal Ministry of Education & Research (BMBF) [05K19WC1]; Deutsche Forschungsgemeinschaft (DFG)German Research Foundation (DFG) [DU 954-11/1, DU 393-9/2, DU 393-13/1]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]</p>","<p>Based on the results from previous high-pressure experiments on the gadolinite-type mineral datolite, CaBSiO4(OH), the behavior of the isostructural borates beta-HfB2O5 and beta-ZrB2O5 have been studied by synchrotron-based in situ high-pressure single-crystal X-ray diffraction experiments. On compression to 120 GPa, both borate layer-structures are preserved. Additionally, at approximate to 114 GPa, the formation of a second phase can be observed in both compounds. The new high-pressure modification gamma-ZrB2O5 features a rearrangement of the corner-sharing BO4 tetrahedra, while still maintaining the four- and eight-membered rings. The new phase gamma-HfB2O5 contains ten-membered rings including the rare structural motif of edge-sharing BO4 tetrahedra with exceptionally short B-O and B...B distances. For both structures, unusually high coordination numbers are found for the transition metal cations, with ninefold coordinated Hf4+, and tenfold coordinated Zr4+, respectively. These findings remarkably show the potential of cold compression as a low-energy pathway to discover metastable structures that exhibit new coordinations and structural motifs.</p>","","","","","","","","","","","","","2021-03-21","2021-03-21","2021-04-15","http://liu.diva-portal.org/smash/get/diva2:1538777/FULLTEXT01.pdf","","5","","2","","","","","","false","","",""
"1545801","Zaleski, Karol (Adam Mickiewicz Univ, Poland);Ekholm, Marcus [marek10] [0000-0002-7563-1494] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci & Technol MISIS, Russia);Dubowik, Janusz (Polish Acad Sci, Poland)","Local atomic configuration approach to the nonmonotonic concentration dependence of magnetic properties of Ni(2)Mn(1+x)Z(1-x) (Z = In, Sn, Sb) Heusler alloys","Artikel i tidskrift","Refereegranskat","eng","Scripta Materialia","1359-6462","1872-8456","published","194","","","","","2021","","","","PERGAMON-ELSEVIER SCIENCE LTD","","","","","","","10.1016/j.scriptamat.2020.113646","000632783300035","","","urn:nbn:se:liu:diva-175083","","","Heusler phases; Ferromagnetic shape memory alloy; Magnetic thin films; Magnetic structure; Ab initio calculation","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Polish National Science Centre [DEC-2014/15/B/ST3/02927]; Strategic Research Areas the Swedish eScience Research Centre (SeRC); Advanced Functional Materials at Linkoping University (Faculty Grant SFOMatLiU) [2009 00971]; Ministry of Science and Higher Education of the Russian Federation of NUST ""MISIS"" [K2-2019-001, 211]</p>","<p>The Ni(2)Mn(1+x)Z(1-x) Heusler alloys, where Z = In, Sn, Sb are attractive candidates for shape memory applications. The effect is directly related to their magnetic properties. We have studied these systems by ab-initio calculations and experiments, focusing on magnetic moments and exchange-bias fields. The calculations indicate that the composition dependence of the total magnetic moment is due to competing ferro-magnetic and antiferromagnetic alignment between Mn atoms on different sublattices and with different local environments. This phenomenon can also explain the composition dependence of the exchange-bias effect. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.</p>","","","","","","","","","","","","","2021-04-20","2021-04-20","2021-04-20","","","5","","2","","","","","113646","true","","",""
"1541701","Laniel, Dominique (Univ Bayreuth, Germany);Winkler, Bjoern (Goethe Univ Frankfurt, Germany);Koemets, Egor (Univ Bayreuth, Germany);Fedotenko, Timofey (Univ Bayreuth, Germany);Chariton, Stella (Univ Chicago, IL 60637 USA);Milman, Victor (Dassault Syst BIOVIA, England);Glazyrin, Konstantin (DESY, Germany);Prakapenka, Vitali (Univ Chicago, IL 60637 USA);Dubrovinsky, Leonid (Univ Bayreuth, Germany);Doubrovinckaia, Natalia [natdo06] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Bayreuth, Germany)","Nitrosonium nitrate (NO+NO3-) structure solution using in situ single-crystal X-ray diffraction in a diamond anvil cell","Artikel i tidskrift","Refereegranskat","eng","IUCrJ","0972-6918","2052-2525","published","8","","","208","214","2021","","","","International Union of Crystallography","","","","","","","10.1107/S2052252521000075","000625872900010","33708398","","urn:nbn:se:liu:diva-174781","","","nitrosonium nitrate; high-pressure single-crystal X-ray diffraction; positively charged oxygen atoms; structure refinement","Strukturbiologi (10601)","","","<p>Funding Agencies|Alexander von Humboldt FoundationAlexander von Humboldt Foundation; Federal Ministry of Education and Research, Germany (BMBF)Federal Ministry of Education & Research (BMBF) [05K19WC1]; Deutsche Forschungsgemeinschaft (DFG)German Research Foundation (DFG) [DU 954-11/1, DU 393-9/2, DU 393-13/1]; DFGGerman Research Foundation (DFG)European Commission [DFG FOR2125, WI1232]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]</p>","<p>At high pressures, autoionization - along with polymerization and metallization - is one of the responses of simple molecular systems to a rise in electron density. Nitrosonium nitrate (NO+NO3-), known for this property, has attracted a large interest in recent decades and was reported to be synthesized at high pressure and high temperature from a variety of nitrogen-oxygen precursors, such as N2O4, N2O and N-2-O-2 mixtures. However, its structure has not been determined unambiguously. Here, we present the first structure solution and refinement for nitrosonium nitrate on the basis of single-crystal X-ray diffraction at 7.0 and 37.0 GPa. The structure model (P2(1)/m space group) contains the triple-bonded NO+ cation and the NO3- sp(2)-trigonal planar anion. Remarkably, crystal-chemical considerations and accompanying density-functional-theory calculations show that the oxygen atom of the NO+ unit is positively charged - a rare occurrence when in the presence of a less-electronegative element.</p>","","","","","","","","","","","","","2021-04-01","2021-04-01","2021-04-22","http://liu.diva-portal.org/smash/get/diva2:1541701/FULLTEXT01.pdf","","10","","1","","","","","","false","","",""
"1422729","Skripnyak, Vladimir A. (Natl Res Tomsk State Univ, Russia);Skripnyak, Vladimir V. (Natl Res Tomsk State Univ, Russia);Skripnyak, Evgeniya G. (Natl Res Tomsk State Univ, Russia);Skripnyak, Natalia [natsk33] [0000-0003-1634-5882] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Res Tomsk State Univ, Russia)","Modelling of the mechanical response of Zr-Nb and Ti-Nb alloys in a wide temperature range","Artikel i tidskrift","Refereegranskat","eng","International Journal of Mechanics and Materials in Design","1569-1713","1573-8841","published","16","1","","215","224","2020","","","","SPRINGER HEIDELBERG","","","","","","","10.1007/s10999-019-09447-z","000520308500015","","","urn:nbn:se:liu:diva-165006","","","Yield stress; Strain rate sensitivity; Ultra-fine grained structure; Elevated temperature; Zirconium-niobium alloys; Titanium-niobium alloys","Fysik (103)","","","<p>Funding Agencies|Russian Science Foundation (RSF)Russian Science Foundation (RSF) [18-71-00117]</p>","<p>This article presents the results of modeling the mechanical behavior of Zr-Nb and Ti-Nb alloys in a range of strain rates from 0.001 to 1000 1/s and temperature range 297-1273 K. A modification of constitutive equations describing the mechanical response of fine-grained and coarse-grained Zr-1Nb and Ti-13Nb-13Zr alloys in a wide temperature range is proposed. It was shown that the phase transition between the hexagonal closed packed and body-centered cubic crystal structure at elevated temperatures leads to a sharp change in strain rate sensitivity of the yield strength of Zr-Nb and Ti-Nb alloys. The proposed modifications of constitutive equations make it possible to describe the strain hardening and the strain rate sensitivity of the plastic flow stress over a wide temperature range in the coarse-crystalline and ultrafine-grained Zr-Nb and Ti-Nb alloys. The results can be used for engineering analysis of structural elements of technical systems and design of manufacturing technologies for biomedical products.</p>","","","","","","","","","","","","","2020-04-08","2020-04-08","2020-04-08","","","4","","1","","","","","","false","","",""
"1423722","Ekström, Erik [eriek66] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Le Febvrier, Arnaud [arnle40] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Bourgeois, F. (Univ Technol Blois, France);Lundqvist, Björn [bjolu18] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Palisaitis, Justinas [juspa01] [0000-0003-3203-7935] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Persson, Per O A [perpe25] [0000-0001-9140-6724] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Caballero-Calero, O. (CEI UAM, Spain);Martin-Gonzalez, M. S. (CEI UAM, Spain);Klarbring, Johan [johkl85] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Eriksson, Fredrik [freer90] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Paul, Biplab [bippa36] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Eklund, Per [perek02] [0000-0003-1785-0864] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902])","The effects of microstructure, Nb content and secondary Ruddlesden-Popper phase on thermoelectric properties in perovskite CaMn1-xNbxO3 (x=0-0.10) thin films","Artikel i tidskrift","Refereegranskat","eng","RSC Advances","2046-2069","2046-2069","published","10","13","","7918","7926","2020","","","","Royal Society of Chemistry","","","","","","","10.1039/c9ra10007e","000519586300056","","2-s2.0-85081135650","urn:nbn:se:liu:diva-165095","","","","Materialkemi (10403)","","","<p>Funding Agencies|Swedish Foundation for Strategic Research (SSF) through the Future Research Leaders 5 program; Swedish Research Council (VR)Swedish Research Council [2016-03365, 2014-4750]; Knut and Alice Wallenberg Foundation through the Wallenberg Academy Fellows program; Electron Microscopy Laboratory at Linkoping University; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; Swedish Energy AgencySwedish Energy Agency [46519-1]; Spanish MinistrySpanish Government [MAT2017-86450-C4-3-R]</p>","<p>CaMn1-xNbxO3 (x = 0, 0.5, 0.6, 0.7 and 0.10) thin films have been grown by a two-step sputtering/annealing method. First, rock-salt-structured (Ca,Mn1-x,Nb-x)O thin films were deposited on 11 & x304;00 sapphire using reactive RF magnetron co-sputtering from elemental targets of Ca, Mn and Nb. The CaMn1-xNbxO3 films were then obtained by thermally induced phase transformation from rock-salt-structured (Ca,Mn1-xNbx)O to orthorhombic during post-deposition annealing at 700 degrees C for 3 h in oxygen flow. The X-ray diffraction patterns of pure CaMnO3 showed mixed orientation, while Nb-containing films were epitaxially grown in [101] out of-plane-direction. Scanning transmission electron microscopy showed a Ruddlesden-Popper (R-P) secondary phase in the films, which results in reduction of the electrical and thermal conductivity of CaMn1-xNbxO3. The electrical resistivity and Seebeck coefficient of the pure CaMnO3 film were measured to 2.7 omega cm and -270 mu V K-1 at room temperature, respectively. The electrical resistivity and Seebeck coefficient were reduced by alloying with Nb and was measured to 0.09 omega cm and -145 mu V K-1 for x = 0.05. Yielding a power factor of 21.5 mu W K-2 m(-1) near room temperature, nearly eight times higher than for pure CaMnO3 (2.8 mu W K-2 m(-1)). The power factors for alloyed samples are low compared to other studies on phase-pure material. This is due to high electrical resistivity originating from the secondary R-P phase. The thermal conductivity of the CaMn1-xNbxO3 films is low for all samples and is the lowest for x = 0.07 and 0.10, determined to 1.6 W m(-1) K-1. The low thermal conductivity is attributed to grain boundary scattering and the secondary R-P phase.</p>","","","","","","","","","","","","","2020-04-15","2020-04-15","2020-05-07","http://liu.diva-portal.org/smash/get/diva2:1423722/FULLTEXT01.pdf","","13","","1","","","","","","true","","",""
"1426804","Ektarawong, A. (Chulalongkorn Univ, Thailand; Minist Higher Educ Sci Res and Innovat, Thailand);Bovornratanaraks, T. (Chulalongkorn Univ, Thailand; Minist Higher Educ Sci Res and Innovat, Thailand);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Role of spin-orbit coupling in the alloying behavior of multilayer Bi1-xSbx solid solutions revealed by a first-principles cluster expansion","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","101","13","","","","2020","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.101.134104","000525325800001","","","urn:nbn:se:liu:diva-165328","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Chulalongkorn UniversityChulalongkorn University [CUGR_62_66_23_26]; Thailand Toray Science Foundation (TTSF); Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; Swedish Foundation for Strategic Research through the Future Research Leaders 6 program [FFL 15-0290]; Swedish Research Council (VR)Swedish Research Council [2019-05403]; Knut and Alice Wallenberg Foundation (Wallenberg Scholar Grant) [KAW-2018.0194]</p>","<p>We employ a first-principles cluster-expansion method in combination with canonical Monte Carlo simulations to study the effect of spin-orbit coupling on the alloying behavior of multilayer Bi1-xSbx. Our simulations reveal that spin-orbit coupling plays an essential role in determining the configurational thermodynamics of Bi and Sb atoms. Without the presence of spin-orbit coupling, Bi1-xSbx is predicted to exhibit at low-temperature chemical ordering of Bi and Sb atoms, leading to formation of an ordered structure at x approximate to 0.5. Interestingly, the spin-orbit-coupling effect intrinsically induced by the existence of Bi and Sb results in the disappearance of chemical ordering of the constituent elements within an immiscible region existing at T &lt; 370 K, and consequently Bi1-xSbx displays merely a tendency toward local segregation of Bi and Sb atoms, resulting in coexistence of Bi-rich and Sb-rich Bi1-xSbx solid solutions without the formation of any ordered structure of Bi1-xSbx as predicted in the absence of spin-orbit coupling. These findings distinctly highlight an influence of spin-orbit coupling on the alloying behavior of Bi1-xSbx and probably other alloys composed of heavy elements, where the spin-orbit-coupling effect is supposed to be robust.</p>","","","","","","","","","","","","","2020-04-27","2020-04-27","2020-05-27","http://liu.diva-portal.org/smash/get/diva2:1426804/FULLTEXT01.pdf","","3","","2","","","","","134104","false","","",""
"1428593","Belov, M. P. (Natl Univ Sci and Technol MISIS, Russia);Syzdykova, A. B. (Natl Univ Sci and Technol MISIS, Russia);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Temperature-dependent lattice dynamics of antiferromagnetic and ferromagnetic phases of FeRh","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","101","13","","","","2020","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.101.134303","000526035200003","","","urn:nbn:se:liu:diva-165473","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Ministry of Science and High Education of the Russian Federation [K2-2019-001, 211]; Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR) [19-02-00871]; Swedish Research Council (VR)Swedish Research Council [2019-05600]</p>","<p>We have investigated lattice dynamics of antiferromagnetic and ferromagnetic phases of cubic (B2) FeRh at various temperatures from first principles using the temperature-dependent effective potential method. We have shown that already at low temperature the cubic structure of the antiferromagnetic phase becomes dynamically stable, which eliminates the contradiction between experimental observations and previous theoretical results showing its dynamical instability at temperature T = 0 K. In addition, we have observed a significant difference in the temperature dependence of lattice vibrations of the ferromagnetic and antiferromagnetic phases. The phonon spectrum of the FM phase softens much stronger than that of the AFM phase, which provides additional contribution to the increase of vibrational entropy of the FM phase at high temperatures. The calculated difference between the vibrational entropies of the FM and AFM phases at a metamagnetic transition temperature (350 K) is 16 J/kg/K. This value is comparable with the experimental value of the total entropy change. We therefore conclude that the lattice dynamics plays a decisive role in the metamagnetic phase transition in FeRh and its remarkable magnetocaloric properties.</p>","","","","","","","","","","","","","2020-05-06","2020-05-06","2020-05-29","http://liu.diva-portal.org/smash/get/diva2:1428593/FULLTEXT01.pdf","","3","","2","","","","","134303","false","","",""
"1428595","Ivády, Viktor [vikiv58] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Wigner Res Ctr Phys, Hungary)","Longitudinal spin relaxation model applied to point-defect qubit systems","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","101","15","","","","2020","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.101.155203","000526523200002","","","urn:nbn:se:liu:diva-165472","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|MTA Premium Postdoctoral Research Program; Knut and Alice Wallenberg Foundation through WBSQD2 project [2018.0071]; Hungarian NKFIH Grant of the National Excellence Program of Quantum-coherent materials project [KKP129866]; NKFIH through the National Quantum Technology Program [2017-1.2.1-NKP-2017-00001]; EU QuantERA Q_magine project (NKFIH Grant) [127889]</p>","<p>Controllable, partially isolated few-level systems in semiconductors have recently gained multidisciplinary attention due to their widespread nanoscale sensing and quantum technology applications. Quantitative simulation of the dynamics and related applications of such systems is a challenging theoretical task that requires faithful description not only of the few-level systems but also their local environments. Here, we develop a method that can describe relevant relaxation processes induced by a dilute bath of nuclear and electron spins. The method utilizes an extended Lindblad equation in the framework of cluster approximation of a central spin system. We demonstrate that the proposed method can accurately describe T-1 time of an exemplary solid-state point-defect qubit system, in particular, the nitrogen-vacancy (NV) center in diamond, at various magnetic fields and strain.</p>","","","","","","","","","","","","","2020-05-06","2020-05-06","2020-05-29","http://liu.diva-portal.org/smash/get/diva2:1428595/FULLTEXT01.pdf","","1","","2","","","","","155203","false","","",""
"1429521","Ivády, Viktor [vikiv58] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Wigner Res Ctr Phys, Hungary);Barcza, Gergely (Wigner Res Ctr Phys, Hungary; Acad Sci Czech Republ, Czech Republic);Thiering, Gergo (Wigner Res Ctr Phys, Hungary);Li, Song (City Univ Hong Kong, Peoples R China);Hamdi, Hanen (Wigner Res Ctr Phys, Hungary);Chou, Jyh-Pin (City Univ Hong Kong, Peoples R China);Legeza, Ors (Wigner Res Ctr Phys, Hungary);Gali, Adam (Wigner Res Ctr Phys, Hungary; Budapest Univ Technol and Econ, Hungary)","Ab initio theory of the negatively charged boron vacancy qubit in hexagonal boron nitride","Artikel i tidskrift","Refereegranskat","eng","NPJ COMPUTATIONAL MATERIALS","2057-3960","","published","6","1","","","","2020","","","","Nature Publishing Group","","","","","","","10.1038/s41524-020-0305-x","000528385800001","","2-s2.0-85083862127","urn:nbn:se:liu:diva-165650","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|MTA Premium Postdoctoral Research Program; Knut and Alice Wallenberg Foundation through WBSQD2 project [2018.0071]; NKFIH [PD-17-125261, K120569]; ""Bolyai"" Research Scholarship of HAS; Alexander von Humboldt FoundationAlexander von Humboldt Foundation; Hungarian NKFIH of the National Excellence Program of Quantum-coherent materials project [KKP129866]; NKFIH through the National Quantum Technology Program [2017-1.2.1-NKP-2017-00001]</p>","<p>Highly correlated orbitals coupled with phonons in two-dimension are identified for paramagnetic and optically active boron vacancy in hexagonal boron nitride by first principles methods which are responsible for recently observed optically detected magnetic resonance signal. Here, we report ab initio analysis of the correlated electronic structure of this center by density matrix renormalization group and Kohn-Sham density functional theory methods. By establishing the nature of the bright and dark states as well as the position of the energy levels, we provide a complete description of the magneto-optical properties and corresponding radiative and non-radiative routes which are responsible for the optical spin polarization and spin dependent luminescence of the defect. Our findings pave the way toward advancing the identification and characterization of room temperature quantum bits in two-dimensional solids.</p>","","","","","","","","","","","","","2020-05-11","2020-05-11","2020-06-02","http://liu.diva-portal.org/smash/get/diva2:1429521/FULLTEXT01.pdf","","8","","0","","","","","41","true","","",""
"1415795","da Silva, A. Ferreira (Univ Fed Bahia, Brazil; Univ Sao Paulo, Brazil);Toloza Sandoval, M. A. (Univ Fed Bahia, Brazil);Levine, A. (Univ Sao Paulo, Brazil);Levinson, E. (Univ Sao Paulo, Brazil);Boudinov, H. (Univ Fed Rio Grande do Sul, Brazil);Sernelius, Bo [bose02] [0000-0002-6281-868X] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Heavily n-doped Ge: Low-temperature magnetoresistance properties on the metallic side of the metal-nonmetal transition","Artikel i tidskrift","Refereegranskat","eng","Journal of Applied Physics","0021-8979","1089-7550","published","127","4","","","","2020","","","","AMER INST PHYSICS","","","","","","","10.1063/1.5125882","000515698500045","","","urn:nbn:se:liu:diva-164396","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Brazilian agency: CNPqNational Council for Scientific and Technological Development (CNPq) [303304/2010-3]; Brazilian agency: CAPESCAPES [PNPD 88882.306206/2018-01]; Brazilian agency: FAPESB [PNX 0007/2011, INT 0003/2015]; Brazilian agency: FAPESPFundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP) [15/16191-5]</p>","<p>We report here an experimental and theoretical study on the magnetoresistance properties of heavily phosphorous doped germanium on the metallic side of the metal-nonmetal transition. An anomalous regime, formed by negative values of the magnetoresistance, was observed by performing low-temperature measurements and explained within the generalized Drude model, due to the many-body effects. It reveals a key mechanism behind the magnetoresistance properties at low temperatures and, therefore, constitutes a path to its manipulation in such materials of great interest in fundamental physics and technological applications. Published under license by AIP Publishing.</p>","","","","","","","","","","","","","2020-03-19","2020-03-19","2020-06-03","http://liu.diva-portal.org/smash/get/diva2:1415795/FULLTEXT01.pdf","","6","","1","","","","","045705","false","","",""
"1444139","Laniel, Dominique (Univ Bayreuth, Germany);Winlder, Bioern (Goethe Univ Frankfurt, Germany);Fedotenko, Timofey (Univ Bayreuth, Germany);Pakhomova, Anna (DESY, Germany);Chariton, Stella (Univ Chicago, IL 60637 USA);Milman, Victor (Dassault Syst BIOVIA, England);Prakapenka, Vitali (Univ Chicago, IL 60637 USA);Dubrovinsky, Leonid (Univ Bayreuth, Germany);Doubrovinckaia, Natalia [natdo06] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Bayreuth, Germany)","High-Pressure Polymeric Nitrogen Allotrope with the Black Phosphorus Structure","Artikel i tidskrift","Refereegranskat","eng","Physical Review Letters","0031-9007","1079-7114","published","124","21","","","","2020","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevLett.124.216001","000535862200009","32530671","","urn:nbn:se:liu:diva-166477","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|Alexander von Humboldt FoundationAlexander von Humboldt Foundation; Federal Ministry of Education and Research, Germany (BMBF)Federal Ministry of Education & Research (BMBF) [5K16WC1, 05K19WC1]; Deutsche Forschungsgemeinschaft (DFG)German Research Foundation (DFG) [DU 954-11/1, DU 393-9/2, DU 393-13/1]; DFGGerman Research Foundation (DFG) [DFG FOR2125, WI1232]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]</p>","<p>Studies of polynitrogen phases are of great interest for fundamental science and for the design of novel high energy density materials. Laser heating of pure nitrogen at 140 GPa in a diamond anvil cell led to the synthesis of a polymeric nitrogen allotrope with the black phosphorus structure, bp-N. The structure was identified in situ using synchrotron single-crystal x-ray diffraction and further studied by Raman spectroscopy and density functional theory calculations. The discovery of bp-N brings nitrogen in line with heavier pnictogen elements, resolves incongruities regarding polymeric nitrogen phases and provides insights into polynitrogen arrangements at extreme densities.</p>","","","","","","","","","","","","","2020-06-20","2020-06-20","2020-06-20","","","9","","2","","","","","216001","false","","",""
"1444631","Herper, Heike C. (Uppsala Univ, Sweden);Vekilova, Olga Yu (Uppsala Univ, Sweden);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Di Marco, Igor (Uppsala Univ, Sweden; Asia Pacific Ctr Theoret Phys, South Korea; POSTECH, South Korea);Eriksson, Olle (Uppsala Univ, Sweden; Orebro Univ, Sweden)","Localized versus itinerant character of 4f-states in cerium oxides","Artikel i tidskrift","Refereegranskat","eng","Journal of Physics: Condensed Matter","0953-8984","1361-648X","published","32","21","","","","2020","","","","IOP PUBLISHING LTD","","","","","","","10.1088/1361-648X/ab6e92","000537548500002","31968323","","urn:nbn:se:liu:diva-166855","","","density functional theory; rare-earth compounds; weak localization; oxides","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Swedish Research CouncilSwedish Research Council; Foundation for strategic research (SSF)Swedish Foundation for Strategic Research; eSSENCE; Knut and Alice Wallenberg foundationKnut & Alice Wallenberg Foundation; VR project [2014-4750]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; JRG Program at APCTP through the Science and Technology Promotion Fund of the Korean Government; Korean Local Government-Gyeongsangbuk-do Province; Korean Local Government-Pohang City; STandUP; JRG Program at APCTP through the Lottery Fund of the Korean Government</p>","<p>The electronic structure of cerium oxide is investigated here using a combination of ab initio one-electron theory and elements from many-body physics, with emphasis on the nature of the 4f electron shell of cerium ions. We propose to use the hybridization function as a convenient measure for the degree of localization of the 4f shell of this material, and observe that changing the oxidation state is related to distinct changes in the hybridization between the 4f shell and ligand states. The theory reveals that CeO2 has essentially itinerant 4f states, and that in the least oxidized form of ceria, Ce2O3, the 4f states are almost (but not fully) localized. This conclusion is supported by additional calculations based on a combination of density functional theory and dynamical mean field theory. Most importantly, our model points to the fact that diffusion of oxygen vacancies in cerium oxide may be seen as polaron hopping, involving a correlated 4f electron cloud, which is located primarily on Ce ions of several atomic shells surrounding the vacancy.</p>","","","","","","","","","","","","","2020-06-22","2020-06-22","2020-06-22","","","5","","1","","","","","215502","false","","",""
"1425511","Skripnyak, Natalia [natsk33] [0000-0003-1634-5882] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ponomareva, A. V. (Materials Modeling and Development Laboratory, National University of Science and Technology “MISIS”, Moscow, Russian Federation);Belov, M. P. (Materials Modeling and Development Laboratory, National University of Science and Technology “MISIS”, Moscow, Russian Federation);Syutkin, E. A. (Thermochemistry of Materials SRC, National University of Science and Technology “MISIS”, Moscow, Russian Federation);Khvan, A. V. (Thermochemistry of Materials SRC, National University of Science and Technology “MISIS”, Moscow, Russian Federation);Dinsdale, A. T. (Hampton Thermodynamics Limited, Hampton, Middlesex, United Kingdom);Abrikosov, Igor A. [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Mixing enthalpies of alloys with dynamical instability : bcc Ti-V system","Artikel i tidskrift","Refereegranskat","eng","Acta Materialia","1359-6454","1873-2453","published","188","","","145","154","2020","","","","","","","","","","","10.1016/j.actamat.2020.01.056","000527826500014","","","urn:nbn:se:liu:diva-165265","","","Ti-V alloys;Thermodynamic properties;Molecular dynamics;Enthalpy of mixing;Calorimetry","Den kondenserade materiens fysik (10304)","","","<p>Funding agencies: Swedish Research CouncilSwedish Research Council [201804834]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Link_oping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; Ministry of Science and High Education</p>","<p>Enthalpy of mixing is among the key materials parameters to determine phase stability and phase transformations in solid solutions. The possibility to predict it from first principles in the framework of the density functional theory is one of the corner stones of the modern materials modeling and the future data-driven materials design. Here we have considered body-centered cubic (bcc) Ti-V alloys, a system with high potential for aerospace, automotive biomedical and energy applications, which is known to exhibit the dynamical instability of the crystal lattice for Ti-rich alloys at low temperature. We have calculated the mixing enthalpies ΔH of bcc Ti-V alloys in the whole interval of concentration at high temperature using ab initio molecular dynamics (AIMD) simulations. A comparison with state-of-the-art static calculations at temperature 0 K shows drastic difference between the two methods: while AIMD predicts positive values of ΔH in the whole range of concentrations, the static zero-temperature simulations result in negative values of ΔH for Ti-rich alloys. We have measured the mixing enthalpy of bcc Ti-V alloys experimentally at 1073 K using an isoperibol high temperature Tian-Calvet calorimeter and found that the enthalpies are positive, in agreement with our finite temperature AIMD calculations. We attribute the failure of the standard static calculations of ΔH to lattice distortions associated with the dynamical instability of bcc Ti-V alloys at zero temperature and argue that the effect should be generally important in theoretical predictions of thermodynamic properties, especially for systems with dynamical instability.</p>","","","","","","","","","","","","","2020-04-21","2020-04-21","2020-07-09","","","7","","2","urn:nbn:se:liu:diva-165270","","","","","true","","",""
"1437717","Khandarkhaeva, Saiana (Univ Bayreuth, Germany);Fedotenko, Timofey (Univ Bayreuth, Germany);Bykov, Maxim (Carnegie Inst Sci, DC 20015 USA);Bykova, Elena (Carnegie Inst Sci, DC 20015 USA);Chariton, Stella (Univ Chicago, IL 60637 USA);Sedmak, Pavel (European Synchrotron Radiat Facil, France);Glazyrin, Konstantin (DESY, Germany);Prakapenka, Vitali (Univ Chicago, IL 60637 USA);Doubrovinckaia, Natalia [natdo06] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Bayreuth, Germany);Dubrovinsky, Leonid (Univ Bayreuth, Germany)","Novel Rhenium Carbides at 200 GPa","Artikel i tidskrift","Refereegranskat","eng","European Journal of Inorganic Chemistry","1434-1948","1099-1948","aheadofprint","","","","","","2020","","","","WILEY-V C H VERLAG GMBH","","","","","","","10.1002/ejic.202000252","000532600100001","","","urn:nbn:se:liu:diva-166178","","","Rhenium; Carbon; Carbides; Structure elucidation; High-pressure chemistry","Oorganisk kemi (10404)","","","<p>Funding Agencies|Federal Ministry of Education and Research, Germany (BMBF)Federal Ministry of Education & Research (BMBF) [5K16WC1, 05K19WC1]; Deutsche Forschungsgemeinschaft (DFG)German Research Foundation (DFG) [DU 954-11/1, DU 393-9/2, DU 393-13/1]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]</p>","<p>Laser heating of rhenium in a diamond anvil cell to 3000 +/- 300 K at about 200 GPa results in formation of two previously unknown rhenium carbides, hexagonal WC-type structured ReC and orthorhombic TiSi2-type structured ReC2. The shortest C-C distances [1.758(3) angstrom at 219(5) GPa and 1.850(4) angstrom at 180(7) GPa] found in honeycomb-like carbon nets in the structure of ReC2 are quite unusual. The Re-C solid solution formed at multimegabar pressure has the carbon content of approximate to 20 at%.</p>","","","","","","","","","","","","","2020-06-09","2020-06-09","2020-07-21","http://liu.diva-portal.org/smash/get/diva2:1437717/FULLTEXT01.pdf","","10","","1","","","","","","false","","",""
"1444149","Mei, A. B. (Cornell Univ, NY 14853 USA);Kindlund, H. (Univ Calif Los Angeles, CA 90095 USA);Broitman, Esteban [broes27] [0000-0003-3277-1945] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (SKF, Netherlands);Hultman, Lars [larhu75] [0000-0002-2837-3656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Petrov, Ivan [ivape26] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Illinois, IL 61801 USA);Greene, Joseph E [josgr17] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Illinois, IL 61801 USA; Natl Taiwan Univ Sci and Technol, Taiwan);Sangiovanni, Davide [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Ruhr Univ Bochum, Germany)","Adaptive hard and tough mechanical response in single-crystal B1 VNx ceramics via control of anion vacancies","Artikel i tidskrift","Refereegranskat","eng","Acta Materialia","1359-6454","1873-2453","published","192","","","78","88","2020","","","","PERGAMON-ELSEVIER SCIENCE LTD","","","","","","","10.1016/j.actamat.2020.03.037","000536138600009","","","urn:nbn:se:liu:diva-166467","","","Refractory ceramics; Toughness; Defects; Nanoindentation; Density-functional molecular dynamics","Annan materialteknik (20599)","","","<p>Funding Agencies|Swedish Research CouncilSwedish Research Council [201607213]; VINN Excellence Center Functional Nanoscale Materials (FunMat-2) Grant [2016-05156]; Olle Engkvist Foundation; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation [KAW-2016-0358]; Government Strategic Research Area in Materials Science on Advanced Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]</p>","<p>High hardness and toughness are generally considered mutually exclusive properties for single-crystal ceramics. Combining experiments and ab initio molecular dynamics (AIMD) atomistic simulations at room temperature, we demonstrate that both the hardness and toughness of single-crystal NaCl-structure VNx/MgO(001) thin films are simultaneously enhanced through the incorporation of anion vacancies. Nanoindentation results show that VN0.8, here considered as representative understoichiometric VNx system, is approximate to 20% harder, as well as more resistant to fracture than stoichiometric VN samples. AIMD modeling of VN and VN0.8 supercells subjected to [001] and [110] elongation reveal that the tensile strengths of the two materials are similar. Nevertheless, while the stoichiometric VN phase cleaves in a brittle manner at tensile yield points, the understoichiometric compound activates transformation-toughening mechanisms that dissipate accumulated stresses. AIMD simulations also show that VN0.8 exhibits an initially greater resistance to both {110} &lt; 1 (1) over bar0 &gt; and {111} &lt; 1 (1) over bar0 &gt; shear deformation than VN. However, for progressively increasing shear strains, the VN0.8 mechanical behavior gradually evolves from harder to more ductile than VN. The transition is mediated by anion vacancies, which facilitate {110} &lt; 1 (1) over bar0 &gt; and {111} &lt; 1 (1) over bar0 &gt; lattice slip by reducing activation shear stresses by as much as 35%. Electronic-structure analyses show that the two-regime hard/tough mechanical response of VN0.8 primarily stems from its intrinsic ability to transfer d electrons between 2nd-neighbor and 4th-neighbor (i.e., across vacancy sites) V-V metallic states. Our work offers a route for electronic-structure design of hard materials in which a plastic mechanical response is triggered with loading. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd.</p>","","","","","","","","","","","","","2020-06-20","2020-06-20","2020-08-10","http://liu.diva-portal.org/smash/get/diva2:1444149/FULLTEXT01.pdf","","7","","2","","","","","","false","","",""
"1451682","Leonov, I (Inst Met Phys, Russia; Ural Fed Univ, Russia; Natl Univ Sci and Technol MISIS, Russia);Shorikov, A. O. (Inst Met Phys, Russia; Ural Fed Univ, Russia);Anisimov, V. I (Inst Met Phys, Russia; Ural Fed Univ, Russia);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia)","Emergence of quantum critical charge and spin-state fluctuations near the pressure-induced Mott transition in MnO, FeO, CoO, and NiO","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","101","24","","","","2020","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.101.245144","000540910900001","","","urn:nbn:se:liu:diva-167287","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Russian Science FoundationRussian Science Foundation (RSF) [18-12-00492]; Minobrnauki of Russia [AAAA-A18-118020190098-5]; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation [KAW-2018.0194]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFOMatLiU) [2009 00971]; Swedish e-Science Research Centre (SeRC)</p>","<p>We perform a comprehensive theoretical study of the pressure-induced evolution of the electronic structure, magnetic state, and phase stability of the late transition metal monoxides MnO, FeO, CoO, and NiO using a fully charge self-consistent DFT-Pdynamical mean-field theory method. Our results reveal that the pressure-induced Mott insulator-to-metal phase transition in MnO-NiO is accompanied by a simultaneous collapse of local magnetic moments and lattice volume, implying a complex interplay between chemical bonding and electronic correlations. We compute the pressure-induced evolution of relative weights of the different valence states and spin-state configurations. Employing the concept of fluctuating valence in a correlated solid, we demonstrate that in MnO, FeO, and CoO a Mott insulator-metal transition and collapse of the local moments is accompanied by a sharp crossover of the spin-state and valence configurations. Our microscopic explanation of the magnetic collapse differs from the accepted picture and points out a remarkable dynamical coexistence (frustration) of the high-, intermediate-, and low-spin states. In particular, in MnO, the magnetic collapse is found to be driven by the appearance of the intermediate-spin state (IS), competing with the low-spin (LS) state; in FeO, we observe a conventional high-spin to low-spin (HS-LS) crossover. Most interestingly, in CoO, we obtain a remarkable (dynamical) coexistence of the HS and LS states, i.e., a HS-LS frustration, up to high pressure. Our results demonstrate the importance of quantum fluctuations of the valence and spin states for the understanding of quantum criticality of the Mott transitions.</p>","","","","","","","","","","","","","2020-07-03","2020-07-03","2020-08-21","http://liu.diva-portal.org/smash/get/diva2:1451682/FULLTEXT01.pdf","","4","","2","","","","","245144","false","","",""
"1460185","Okawachi, Yoshitomo (Columbia Univ, NY 10027 USA);Yu, Mengjie (Harvard Univ, MA 02138 USA);Desiatov, Boris (Harvard Univ, MA 02138 USA);Kim, Bok Young (Columbia Univ, NY 10027 USA);Hansson, Tobias [tobha84] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Loncar, Marko (Harvard Univ, MA 02138 USA);Gaeta, Alexander L. (Columbia Univ, NY 10027 USA)","Chip-based self-referencing using integrated lithium niobate waveguides","Artikel i tidskrift","Refereegranskat","eng","Optica","2334-2536","","published","7","6","","702","707","2020","","","","OPTICAL SOC AMER","","","","","","","10.1364/OPTICA.392363","000550698300020","","","urn:nbn:se:liu:diva-168265","","","","Atom- och molekylfysik och optik (10302)","","","<p>Funding Agencies|National Science FoundationNational Science Foundation (NSF) [IIP-1827720]; Defense Advanced Research Projects AgencyUnited States Department of DefenseDefense Advanced Research Projects Agency (DARPA) [W31P4Q-15-1-0013]; Air Force Office of Scientific ResearchUnited States Department of DefenseAir Force Office of Scientific Research (AFOSR) [FA9550-15-1-0303, FA9550-19-1-0310, FA9550-19-1-0376]; VetenskapsradetSwedish Research Council [2017-05309]</p>","<p>The measurement and stabilization of the carrier-envelope offset frequency f(CEO) via self-referencing is paramount for optical frequency comb generation, which has revolutionized precision frequency metrology, spectroscopy, and optical clocks. Over the past decade, the development of chip-scale platforms has enabled compact integrated waveguides for supercontinuum generation. However, there is a critical need for an on-chip self-referencing system that is adaptive to different pump wavelengths, requires low pulse energy, and does not require complicated processing. Here, we demonstrate efficient f(CEO) stabilization of a modelocked laser with only 10(7) pJ of pulse energy via self-referencing in an integrated lithium niobate waveguide. We realize an f-2f interferometer through second-harmonic generation and subsequent supercontinuum generation in a single dispersion-engineered waveguide with a stabilization performance equivalent to a conventional off-chip module. The f(CEO) beatnote is measured over a pump wavelength range of 70 nm. We theoretically investigate our system using a single nonlinear envelope equation with contributions from both second and third-order nonlinearities. Our modeling reveals rich ultrabroadband nonlinear dynamics and confirms that the initial second-harmonic generation followed by supercontinuum generation with the remaining pump is responsible for the generation of a strong f(CEO) signal as compared to a traditional f-2f interferometer. Our technology provides a highly simplified system that is robust, low in cost, and adaptable for precision metrology for use outside a research laboratory. (C) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement</p>","","","","","","","","","","","","","2020-08-22","2020-08-22","2020-09-09","","","7","","0","","","","","","false","","",""
"1459498","Aprilis, Georgios (Univ Bayreuth, Germany);Pakhomova, Anna (Deutsch Elektronen Synchrotron DESY, Germany);Chariton, Stella (Univ Bayreuth, Germany);Khandarkhaeva, Saiana (Univ Bayreuth, Germany);Melai, Caterina (Univ Bayreuth, Germany);Bykova, Elena (Deutsch Elektronen Synchrotron DESY, Germany);Bykov, Maxim (Univ Bayreuth, Germany);Fedotenko, Timofey (Univ Bayreuth, Germany);Koemets, Egor (Univ Bayreuth, Germany);McCammon, Catherine (Univ Bayreuth, Germany);Chumakov, Aleksandr I (ESRF European Synchrotron, France);Hanfland, Michael (ESRF European Synchrotron, France);Doubrovinckaia, Natalia [natdo06] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Bayreuth, Germany);Dubrovinsky, Leonid (Univ Bayreuth, Germany)","The Effect of Pulsed Laser Heating on the Stability of Ferropericlase at High Pressures","Artikel i tidskrift","Refereegranskat","eng","Minerals","2075-163X","2075-163X","published","10","6","","","","2020","","","","MDPI","","","","","","","10.3390/min10060542","000553474600001","","","urn:nbn:se:liu:diva-168292","","","ferropericlase; laser-heated diamond anvil cell (LHDAC); lower mantle; diamond anvil cell; pulsed laser heating","Atom- och molekylfysik och optik (10302)","","","<p>Funding Agencies|Federal Ministry of Education and Research, Germany (BMBF)Federal Ministry of Education & Research (BMBF) [5K16WC1, 05K19WC1]; Deutsche Forschungsgemeinschaft (DFG)German Research Foundation (DFG) [DU 954-11/1, DU 393-9/2, DU 393-13/1]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University faculty grant SFO-Mat-LiU [2009 00971]</p>","<p>It is widely accepted that the lower mantle consists of mainly three major minerals-ferropericlase, bridgmanite and calcium silicate perovskite. Ferropericlase ((Mg,Fe)O) is the second most abundant of the three, comprising approximately 16-20 wt% of the lower mantle. The stability of ferropericlase at conditions of the lowermost mantle has been highly investigated, with controversial results. Amongst other reasons, the experimental conditions during laser heating (such as duration and achieved temperature) have been suggested as a possible explanation for the discrepancy. In this study, we investigate the effect of pulsed laser heating on the stability of ferropericlase, with a geochemically relevant composition of Mg0.76Fe0.24O (Fp24) at pressure conditions corresponding to the upper part of the lower mantle and at a wide temperature range. We report on the decomposition of Fp24 with the formation of a high-pressure (Mg,Fe)(3)O(4)phase with CaTi2O4-type structure, as well as the dissociation of Fp24 into Fe-rich and Mg-rich phases induced by pulsed laser heating. Our results provide further arguments that the chemical composition of the lower mantle is more complex than initially thought, and that the compositional inhomogeneity is not only a characteristic of the lowermost part, but includes depths as shallow as below the transition zone.</p>","","","","","","","","","","","","","2020-08-20","2020-08-20","2020-09-10","http://liu.diva-portal.org/smash/get/diva2:1459498/FULLTEXT01.pdf","","14","","1","","","","","542","true","","",""
"1459895","Klarbring, Johan [johkl85] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Hellman, Olle [olohe96] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci & Technol NUST MISIS, Russia);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Anharmonicity and Ultralow Thermal Conductivity in Lead-Free Halide Double Perovskites","Artikel i tidskrift","Refereegranskat","eng","Physical Review Letters","0031-9007","1079-7114","published","125","4","","","","2020","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevLett.125.045701","000550580800007","32794779","","urn:nbn:se:liu:diva-168283","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|Swedish Research Council (VR)Swedish Research Council [2019-05551]; Swedish Government Strategic Research Area in Materials Science on Advanced Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; Swedish e-science Research Centre (SeRC); Knut and Alice Wallenberg Foundation (Wallenberg Scholar Grant) [KAW-2018.0194]; Ministry of Science and High Education of the Russian Federation of National University of Science and Technology (NUST) ""MISIS"" [K2-2019-001, 211]; Swedish Research CouncilSwedish Research Council [2016-07213]</p>","<p>The lead-free halide double perovskite class of materials offers a promising venue for resolving issues related to toxicity of Pb and long-term stability of the lead-containing halide perovskites. We present a first-principles study of the lattice vibrations in Cs2AgBiBr6, the prototypical compound in this class and show that the lattice dynamics of Cs2AgBiBr6 is highly anharmonic, largely in regards to tilting of AgBr6 and BiBr6 octahedra. Using an energy- and temperature-dependent phonon spectral function, we then show how the experimentally observed cubic-to-tetragonal phase transformation is caused by the collapse of a soft phonon branch. We finally reveal that the softness and anharmonicity of Cs2AgBiBr6 yield an ultralow thermal conductivity, unexpected of high-symmetry cubic structures.</p>","","","","","","","","","","","","","2020-08-21","2020-08-21","2020-09-10","http://liu.diva-portal.org/smash/get/diva2:1459895/FULLTEXT01.pdf","","4","","2","","","","","045701","false","","",""
"1465434","Hansson, Tobias [tobha84] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Tonello, Alessandro (Université de Limoges, XLIM, Limoges, France);Mansuryan, Tigran (Université de Limoges, XLIM, Limoges, France);Mangini, Fabio (Dipartimento di Ingegneria dell’Informazione, University of Brescia, Brescia, Italy);Zitelli, Mario (Dipartimento di Ingegneria dell’Informazione, University of Brescia, Brescia, Italy);Ferraro, Mario (Dipartimento di Ingegneria dell’Informazione, Elettronica e Telecomunicazioni, Sapienza University of Rome, Rome, Italy);Niang, Alioune (Dipartimento di Ingegneria dell’Informazione, University of Brescia, Brescia, Italy);Crescenzi, Rocco (Dipartimento di Ingegneria dell’Informazione, Elettronica e Telecomunicazioni, Sapienza University of Rome, , Italy);Wabnitz, Stefan (Dipartimento di Ingegneria dell’Informazione, Elettronica e Telecomunicazioni, Sapienza University of Rome, Via Eudossiana 18, 00184 Rome, Italy; Novosibirsk State University, Pirogova 1, Novosibirsk 630090, Russia);Couderc, Vincent (Université de Limoges, Limoges, France)","Nonlinear beam self-imaging and self-focusing dynamics in a GRIN multimode optical fiber: theory and experiments","Artikel i tidskrift","Refereegranskat","eng","Optics Express","1094-4087","1094-4087","published","28","16","","24005","24021","2020","","","","Optical Society of America","","","","","","","10.1364/OE.398531","000560931200080","32752387","","urn:nbn:se:liu:diva-169127","","","","Atom- och molekylfysik och optik (10302)","","","<p>Funding Agencies|European Research Council (740355); Agence Nationale de la Recherche (ANR-18-CE080016-01); CILAS Company (ArianeGroup); Vetenskapsrådet (2017-05309); Russian Ministry of Science and Education (14.Y26.31.0017)</p>","<p>Beam self-imaging in nonlinear graded-index multimode optical fibers is of interest for many applications, such as implementing a fast saturable absorber mechanism in fiber lasers via multimode interference. We obtain a new exact solution for the nonlinear evolution of first and second order moments of a laser beam of arbitrary transverse shape carried by a graded-index multimode fiber. We have experimentally directly visualized the longitudinal evolution of beam self-imaging by means of femtosecond laser pulse propagation in both the anomalous and the normal dispersion regime of a standard telecom graded-index multimode optical fiber. Light scattering out of the fiber core via visible photo-luminescence emission permits us to directly measure the self-imaging period and the beam dynamics. Spatial shift and splitting of the self-imaging process under the action of self-focusing are also revealed.</p>","","","","","","","","","","","","","2020-09-09","2020-09-09","2020-09-29","http://liu.diva-portal.org/smash/get/diva2:1465434/FULLTEXT01.pdf","","10","","2","","","","","","false","","",""
"1466191","Casillas Trujillo, Luis [luica08] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Configurational thermodynamics of a 1/2111 screw dislocation core in Mo-W solid solutions using cluster expansion","Artikel i tidskrift","Refereegranskat","eng","Journal of Applied Physics","0021-8979","1089-7550","published","128","4","","","","2020","","","","AMER INST PHYSICS","","","","","","","10.1063/5.0011379","000557315600003","","","urn:nbn:se:liu:diva-168878","","","","Teoretisk kemi (10407)","","","<p>Funding Agencies|Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; Swedish Foundation for Strategic Research through the Future Research Leaders 6 program [FFL 15-0290]; Swedish Research Council (VR)Swedish Research Council [2019-05403]; Knut and Alice Wallenberg Foundation (Wallenberg Scholar Grant) [KAW-2018.0194]</p>","<p>In this work, we have developed a methodology to obtain an ab initio cluster expansion of a system containing a dislocation and studied the effect of configurational disorder on the 1/2111 screw dislocation core structure in disordered Mo1-xWx alloys. Dislocation cores control the selection of glide planes, cross slip, and dislocation nucleation. Configurational disorders in alloys can impact the dislocation core structure and affect dislocation mobility. For our calculations, we have used a quadrupolar periodic array of screw dislocation dipoles and obtained the relaxed structures and energies using density functional theory. We have obtained the dislocation core structure as a function of composition and the interaction energies of solutes with the dislocation as a function of position with respect to the core. With these energies, we performed mean-field calculations to assess segregation toward the core. Finally, with the calculated energies of 1848 alloy configurations with different compositions, we performed a first principle cluster expansion of the configurational energetics of Mo1-xWx solid solutions containing dislocations.</p>","","","","","","","","","","","","","2020-09-11","2020-09-11","2020-09-30","http://liu.diva-portal.org/smash/get/diva2:1466191/FULLTEXT01.pdf","","2","","1","","","","","045114","false","","",""
"1472189","Wasay, Muhammad Abdul (Gwangju Inst Sci & Technol, South Korea; Univ Agr Faisalabad, Pakistan);Johansson, Magnus [magjo23] [0000-0001-6708-1560] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Multichannel asymmetric transmission through a dimer defect with saturable inter-site nonlinearity","Artikel i tidskrift","Refereegranskat","eng","Journal of Physics A: Mathematical and Theoretical","1751-8113","1751-8121","published","53","39","","","","2020","","","","IOP PUBLISHING LTD","","","","","","","10.1088/1751-8121/aba145","000568290200001","","","urn:nbn:se:liu:diva-170155","","","nonlinear dynamics; nonlinear waves; solitons","Matematisk analys (10101)","","","<p>Funding Agencies|MSIT/IITP [1711073835]; GRI; GIST</p>","<p>We consider the asymmetric transmission properties of a discrete nonlinear Schrodinger type dimer with a saturable nonlinear intersite coupling between the dimer sites, in addition to a cubic onsite nonlinearity and asymmetric linear onsite potentials. In contrast to previously studied cases with pure onsite nonlinearities, the transmission coefficient for stationary transmission is shown to be a multivalued function of thetransmittedintensity, in regimes of low saturability and small or moderate transmitted intensity. The corresponding backward transfer map is analyzed analytically and numerically, and shown to have either one or three distinct solutions for saturable coupling, and zero or two solutions for the purely cubic nonlinear coupling. As saturation strength is increased, the multi-solution regimes disappear through bifurcations and the single-valued regime of the onsite model is recovered. The existence of multiple solution branches yields novel mechanisms for asymmetric left/right stationary transmission: in addition to shifts of the positions of transmission peaks, peaks for transmission in one direction may correspond to nonexistence of stationary solutions propagating in the opposite direction, at the corresponding branch and transmitted intensity. Moreover, one of these transmission channels behaves as a nearly perfect mirror for incoming signals. The linear stability of the stationary solutions is analyzed, and instabilities are typically observed, and illustrated by direct numerical simulations, in regimes with large transmission coefficient. Intersite nonlinearities are found to prevent the formation of a localized dimer mode in the instability-induced dynamics. Finally, the partial reflection and transmission of a Gaussian excitation is studied, and the asymmetric transmission properties are compared to previously studied onsite models.</p>","","","","","","","","","","","","","2020-10-01","2020-10-01","2020-10-01","","","2","","1","","","","","395702","false","","",""
"1437695","Bykov, Maxim (Howard Univ, DC 20059 USA; Univ Bayreuth, Germany; Carnegie Inst Sci, DC 20015 USA);Chariton, Stella (Univ Chicago, IL 60437 USA);Bykova, Elena (Carnegie Inst Sci, DC 20015 USA);Khandarkhaeva, Saiana (Univ Bayreuth, Germany);Fedotenko, Timofey (Univ Bayreuth, Germany);Ponomareva, Alena V (Natl Univ Sci and Technol MISIS, Russia);Tidholm, Johan [johti34] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Tasnadi, Ferenc [ferta55] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Sedmak, Pavel (European Synchrotron Radiat Facil, France);Prakapenka, Vitali (Univ Chicago, IL 60437 USA);Hanfland, Michael (European Synchrotron Radiat Facil, France);Liermann, Hanns-Peter (DESY, Germany);Mahmood, Mohammad (Howard Univ, DC 20059 USA);Goncharov, Alexander F. (Carnegie Inst Sci, DC 20015 USA);Doubrovinckaia, Natalia [natdo06] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Bayreuth, Germany);Dubrovinsky, Leonid (Univ Bayreuth, Germany)","High-Pressure Synthesis of Metal-Inorganic Frameworks Hf4N20 center dot N-2, WN8 center dot N-2, and Os5N28 center dot 3 N-2 with Polymeric Nitrogen Linkers","Artikel i tidskrift","Refereegranskat","eng","Angewandte Chemie International Edition","1433-7851","1521-3773","aheadofprint","","","","","","2020","","","","WILEY-V C H VERLAG GMBH","","","","","","","10.1002/anie.202002487","000530869800001","32212190","","urn:nbn:se:liu:diva-166188","","","high-pressure synthesis; inclusion compounds; inorganic double helix; metal-inorganic frameworks; polynitrides","Organisk kemi (10405)","","","<p>Funding Agencies|National Science Foundation-Earth SciencesNational Science Foundation (NSF) [EAR-1634415]; Department of Energy-GeoSciencesUnited States Department of Energy (DOE) [DE-FG02-94ER14466]; Army Research Office; Deutsche Forschungsgemeinschaft (DFG)German Research Foundation (DFG) [DU 95411/1, DU 393-9/2, DU 393-13/1]; Federal Ministry of Education and Research, Germany (BMBF)Federal Ministry of Education & Research (BMBF) [05K19WC1]; Russian Science FoundationRussian Science Foundation (RSF) [18-12-00492]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkcping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; Knut and AliceWallenberg FoundationKnut & Alice Wallenberg Foundation [KAW-2018.0194]; Swedish Research Council (VR)Swedish Research Council [2019-05600]; VINN Excellence Center Functional Nanoscale Materials (FunMat-2) [2016-05156]; [W911NF-19-2-0172]</p>","<p>Polynitrides are intrinsically thermodynamically unstable at ambient conditions and require peculiar synthetic approaches. Now, a one-step synthesis of metal-inorganic frameworks Hf4N20 center dot N2, WN 8 center dot N2, and Os5N28 center dot 3N2 via direct reactions between elements in a diamond anvil cell at pressures exceeding 100 GPa is reported. The porous frameworks (Hf4N20, WN 8, and Os5N28) are built from transition-metal atoms linked either by polymeric polydiazenediyl (polyacetylene-like) nitrogen chains or through dinitrogen units. Triply bound dinitrogen molecules occupy channels of these frameworks. Owing to conjugated polydiazenediyl chains, these compounds exhibit metallic properties. The high-pressure reaction between Hf and N2 also leads to a non-centrosymmetric polynitride Hf2N11 that features double-helix catenapoly[tetraz-1-ene-1,4-diyl] nitrogen chains [-N-N-N=N-](infinity.)</p>","","","","","","","","","","","","","2020-06-09","2020-06-09","2020-10-22","http://liu.diva-portal.org/smash/get/diva2:1437695/FULLTEXT01.pdf","","17","","2","urn:nbn:se:liu:diva-170800","","","","","false","","",""
"1422732","Tidholm, Johan [johti34] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Hellman, Olle [olohe96] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Shulumba, Nina [ninsh46] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Tasnadi, Ferenc [ferta55] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (NUST MISIS, Russia)","Temperature dependence of the Kohn anomaly in bcc Nb from first-principles self-consistent phonon calculations","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","101","11","","","","2020","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.101.115119","000519698100001","","","urn:nbn:se:liu:diva-165001","","","","Fysik (103)","","","<p>Funding Agencies|Swedish Research Council (VR)Swedish Research Council [2015-04391, 2019-05551]; Swedish Government Strategic Research Areas in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; Knut and Alice Wallenberg Foundation (Wallenberg Scholar Grant) [KAW-2018.0194]; Swedish Foundation for Strategic Research (SSF)Swedish Foundation for Strategic Research [EM16-0004]; Russian Science FoundationRussian Science Foundation (RSF) [18-12-00492]</p>","<p>Using ab initio calculations, we have analyzed the influence of anharmonic effects on the electronic structure and the phonon-dispersion relations of body-centered-cubic (bcc) niobium (Nb) and investigated the temperature dependence of the Kohn anomaly in this metal. A comparison of the results obtained in the framework of the temperature-dependent effective potential method with those derived within the quasiharmonic approximation demonstrates the importance of the explicit treatment of the finite-temperature effects upon the theoretical description of bcc Nb lattice dynamics. In agreement with experimental results, the inclusion of anharmonic vibrations in our calculations leads to the disappearance of the Kohn anomaly for the acoustic mode in a vicinity of the Gamma point with increasing temperature. Moreover, the calculated phonon self-energy indicates that the origin of the temperature dependence is related to the change of the electronic structure. We have calculated the temperature dependence of the electronic spectral function and analyzed the Fermi surface of Nb. A significant temperature-induced smearing of the electronic states has been identified as the origin of the disappearance of the Kohn anomaly in Nb at elevated temperature.</p>","","","","","","","","","","","","","2020-04-08","2020-04-08","2020-10-22","http://liu.diva-portal.org/smash/get/diva2:1422732/FULLTEXT01.pdf","","6","","2","urn:nbn:se:liu:diva-170800","","","","115119","false","","",""
"1470906","Stojanovic, M. G. (Univ Belgrade, Serbia);Krasic, M. Stojanovic (Univ Nis, Serbia);Maluckov, A. (Univ Belgrade, Serbia; Inst Basic Sci IBS, South Korea);Johansson, Magnus [magjo23] [0000-0001-6708-1560] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Salinas, I. A. (Univ Chile, Chile);Vicencio, R. A. (Univ Chile, Chile);Stepic, M. (Univ Belgrade, Serbia)","Localized modes in linear and nonlinear octagonal-diamond lattices with two flat bands","Artikel i tidskrift","Refereegranskat","eng","Physical Review A: covering atomic, molecular, and optical physics and quantum information","2469-9926","2469-9934","published","102","2","","","","2020","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevA.102.023532","000565701800001","","","urn:nbn:se:liu:diva-169983","","","","Annan fysik (10399)","","","<p>Funding Agencies|Programa ICM Millennium Institute for Research in Optics (MIRO); FONDECYT GrantComision Nacional de Investigacion Cientifica y Tecnologica (CONICYT)CONICYT FONDECYT [1191205]; Ministry of Education, Science and Technological Development of Republic of Serbia [III45010]</p>","<p>We consider a two-dimensional octagonal-diamond network with a fine-tuned diagonal coupling inside the diamond-shaped unit cell. Its linear spectrum exhibits coexistence of two dispersive bands (DBs) and two flat bands (FBs), touching one of the DBs embedded between them. Analogous to the kagome lattice, one of the FBs will constitute the ground state of the system for a proper sign choice of the Hamiltonian. The system is characterized by two different flat-band fundamental octagonal compactons, originating from the destructive interference of fully geometric nature. In the presence of a nonlinear amplitude (on-site) perturbation, the singleoctagon linear modes continue into one-parameter families of nonlinear compact modes with the same amplitude and phase structure. However, numerical stability analysis indicates that all strictly compact nonlinear modes are unstable, either purely exponentially or with oscillatory instabilities, for weak and intermediate nonlinearities and sufficiently large system sizes. Stabilization may appear in certain ranges for finite systems and, for the compacton originating from the band at the spectral edge, also in a regime of very large focusing nonlinearities. In contrast to the kagome lattice, the latter compacton family will become unstable already for arbitrarily weak defocusing nonlinearity for large enough systems. We show analytically the existence of a critical system size consisting of 12 octagon rings, such that the ground state for weak defocusing nonlinearity is a stable single compacton for smaller systems, and a continuation of a nontrivial, noncompact linear combination of single compacton modes for larger systems. Investigating generally the different nonlinear localized (noncompact) mode families in the semi-infinite gap bounded by this FB, we find that, for increasing (defocusing) nonlinearity the stable ground state will continuously develop into an exponentially localized mode with two main peaks in antiphase. At a critical nonlinearity strength a symmetry-breaking pitchfork bifurcation appears, so that the stable ground state is single peaked for larger defocusing nonlinearities. We also investigate numerically the mobility of localized modes in this regime and find that the considered modes are generally immobile both with respect to axial and diagonal phase-gradient perturbations.</p>","","","","","","","","","","","","","2020-09-26","2020-09-26","2020-10-26","http://liu.diva-portal.org/smash/get/diva2:1470906/FULLTEXT01.pdf","","7","","1","","","","","023532","false","","",""
"1485172","Meier, Thomas (Univ Bayreuth, Germany);Trybel, Florian (Univ Bayreuth, Germany);Criniti, Giacomo (Univ Bayreuth, Germany);Laniel, Dominique (Univ Bayreuth, Germany);Khandarkhaeva, Saiana (Univ Bayreuth, Germany);Koemets, Egor (Univ Bayreuth, Germany);Fedotenko, Timofey (Univ Bayreuth, Germany);Glazyrin, Konstantin (DESY, Germany);Hanfland, Michael (European Synchrotron Radiat Facil ESRF, France);Bykov, Maxim (Howard Univ, DC 20059 USA);Steinle-Neumann, Gerd (Univ Bayreuth, Germany);Doubrovinckaia, Natalia [natdo06] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Bayreuth, Germany);Dubrovinsky, Leonid (Univ Bayreuth, Germany)","Proton mobility in metallic copper hydride from high-pressure nuclear magnetic resonance","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","102","16","","","","2020","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.102.165109","000576053100003","","","urn:nbn:se:liu:diva-170932","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|German Research Foundation (Deutsche Forschungsgemeinschaft, DFG)German Research Foundation (DFG) [DU 954/11-1, DU 393/13-1, DU 393/9-2, ME 5206/3-1, STE 1105/13-1, FOR 2440]; Federal Ministry of Education and Research, Germany (BMBF)Federal Ministry of Education & Research (BMBF) [05K19WC1]; Alexander von Humboldt FoundationAlexander von Humboldt Foundation; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]</p>","<p>The atomic and electronic structures of Cu2H and CuH have been investigated by high-pressure nuclear magnetic resonance spectroscopy up to 96 GPa, X-ray diffraction up to 160 GPa, and density functional theory-based calculations. Metallic Cu2H was synthesized at a pressure of 40 GPa, and semimetallic CuH at 90 GPa, found stable up to 160 GPa. For Cu2H, experiments and computations show an anomalous increase in the electronic density of state at the Fermi level for the hydrogen 1s states and the formation of a hydrogen network in the pressure range 43-58 GPa, together with high H-1 mobility of similar to 10(-7) cm(2)/s. A comparison of these observations with results on FeH suggests that they could be common features in metal hydrides.</p>","","","","","","","","","","","","","2020-11-01","2020-11-01","2020-11-01","","","13","","2","","","","","165109","false","","",""
"1485182","Laniel, Dominique (Univ Bayreuth, Germany);Winkler, Bjoern (Goethe Univ Frankfurt, Germany);Bykova, Elena (DESY, Germany);Fedotenko, Timofey (Univ Bayreuth, Germany);Chariton, Stella (Univ Chicago, IL 60637 USA);Milman, Victor (Dassault Syst BIOVIA, England);Bykov, Maxim (Univ Bayreuth, Germany);Prakapenka, Vitali (Univ Chicago, IL 60637 USA);Dubrovinsky, Leonid (Univ Bayreuth, Germany);Doubrovinckaia, Natalia [natdo06] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Bayreuth, Germany)","Novel sulfur hydrides synthesized at extreme conditions","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","102","13","","","","2020","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.102.134109","000577207300001","","","urn:nbn:se:liu:diva-170921","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Alexander von Humboldt FoundationAlexander von Humboldt Foundation; Federal Ministry of Education and Research, Germany (BMBF)Federal Ministry of Education & Research (BMBF) [05K19WC1]; Deutsche Forschungsgemeinschaft (DFG)German Research Foundation (DFG) [DU 954-11/1, DU 393-9/2, DU 393-13/1]; DFGGerman Research Foundation (DFG) [DFG FOR2125, WI1232]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]</p>","<p>The sulfur-hydrogen system is the first one in which superconductivity at temperatures over 200 K has been reported, albeit at high pressure. The particular phases causing the measured T-c and their structures are not yet firmly identified. Here, synchrotron single-crystal x-ray diffraction studies of S-H samples were performed up to 150 GPa and revealed two previously unobserved and unpredicted sulfur-hydrogen phases-H6 +/- xS5 with x similar to 0.4, and H2.85 +/- yS2 with y similar to 0.35. The crystallographic data obtained in this work, both for the new phases and for the previously identified H3S polymorphs, provide an unambiguous experimental proof of the chemical richness of the S-H system and the structural diversity of compounds forming at high pressures and high temperatures. Our results have profound implications for the interpretation of the resistance, superconductivity, and other physical properties measurements on the complex S-H system.</p>","","","","","","","","","","","","","2020-11-01","2020-11-01","2020-11-01","","","10","","2","","","","","134109","false","","",""
"1476935","Ji, Fuxiang [fuxji90] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Huang, Yuqing [yuqhu58] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Wang, Feng [fenwa69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Kobera, Libor (Czech Acad Sci, Czech Republic);Xie, Fangyan (Sun Yat Sen Univ, Peoples R China);Klarbring, Johan [johkl85] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abbrent, Sabina (Czech Acad Sci, Czech Republic);Brus, Jiri (Czech Acad Sci, Czech Republic);Yin, Chunyang [chuyi94] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci & Technol MISIS, Russia);Buyanova, Irina [iribo40] [0000-0001-7155-7103] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Chen, Weimin [weich55] [0000-0002-6405-9509] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Gao, Feng [fenga88] [0000-0002-2582-1740] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Near-Infrared Light-Responsive Cu-Doped Cs2AgBiBr6","Artikel i tidskrift","Refereegranskat","eng","Advanced Functional Materials","1616-301X","1616-3028","aheadofprint","","","","","","2020","","","","WILEY-V C H VERLAG GMBH","","","","","","","10.1002/adfm.202005521","000570170300001","","","urn:nbn:se:liu:diva-170564","","","Cu doping; lead-free double perovskites; near-infrared absorption; photoconductivity","Atom- och molekylfysik och optik (10302)","","","<p>Funding Agencies|Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation [KAW 2019.0082]; Swedish Energy AgencySwedish Energy Agency [2018-004357]; Grant Agency of the Czech RepublicGrant Agency of the Czech Republic [GA19-05259S]; VR Starting Grant [2019-05279]; Carl Tryggers Stiftelse; Olle Engkvist Byggmastare Stiftelse; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; China Scholarship Council (CSC)China Scholarship Council; Ministry of Science and Higher Education of the Russian Federation of NUST ""MISIS"" [K2-2019-001, 211]; Swedish Research Council (VR)Swedish Research Council [2019-05551]; Swedish Research CouncilSwedish Research Council [2016-07213]</p>","<p>Lead-free halide double perovskites (A(2)B(I)B(III)X(6)) with attractive optical and electronic features are considered to be a promising candidate to overcome the toxicity and stability issues of lead halide perovskites (APbX(3)). However, their poor absorption profiles limit device performance. Here the absorption band edge of Cs(2)AgBiBr(6)double perovskite to the near-infrared range is significantly broadened by developing doped double perovskites, Cs-2(Ag:Cu)BiBr6. The partial replacement of Ag ions by Cu ions in the crystal lattice is confirmed by the X-ray photoelectron spectroscopy (XPS) and solid-state nuclear magnetic resonance (ssNMR) measurements. Cu doping barely affects the bandgap of Cs2AgBiBr6; instead it introduces subbandgap states with strong absorption to the near-infrared range. More interestingly, the near-infrared absorption can generate band carriers upon excitation, as indicated by the photoconductivity measurement. This work sheds new light on the absorption modulation of halide double perovskites for future efficient optoelectronic devices.</p>","","","","","","","","","","","","","2020-10-16","2020-10-16","2020-11-04","http://liu.diva-portal.org/smash/get/diva2:1476935/FULLTEXT01.pdf","","14","","2","","","","","2005521","false","","",""
"1484989","Casillas Trujillo, Luis [luica08] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Gambino, Davide [davga91] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ventelon, Lisa (Univ Paris Saclay, France);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Screw dislocation core structure in the paramagnetic state of bcc iron from first-principles calculations","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","102","9","","","","2020","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.102.094420","000569624900005","","","urn:nbn:se:liu:diva-170637","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Swedish Research Council (VR)Swedish Research Council [2014-6336, 2019-05403]; Marie Sklodowska Curie Actions [INCA 600398]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFOMatLiU) [2009 00971]; Knut and Alice Wallenberg Foundation (Wallenberg Scholar Grant) [KAW-2018.0194]; Swedish Foundation for Strategic Research through the Future Research Leaders 6 program [FFL 15-0290]</p>","<p>Iron-based alloys are widely used as structural components in engineering applications. This calls for a fundamental understanding of their mechanical properties, including those of pure iron. Under operational temperatures the mechanical and magnetic properties will differ from those of ferromagnetic body-centered-cubic iron at 0 K. In this theoretical work we study the effect of disordered magnetism on the screw dislocation core structure and compare with results for the ordered ferromagnetic case. Dislocation cores control some local properties such as the choice of glide plane and the associated dislocation mobility. Changes in the magnetic state can lead to modifications in the structure of the core and affect dislocation mobility. In particular, we focus on the core properties of the 1/2 &lt; 111 &gt; screw dislocation in the paramagnetic state. Using the noncollinear disordered local moment approximation to address paramagnetism, we perform structural relaxations within density functional theory. We obtain the dislocation core structure for the easy and hard cores in the paramagnetic state, and compare them with their ferromagnetic counterparts. By averaging the energy of several disordered magnetic configurations, we obtain an energy difference between the easy- and hard-core configurations, with a lower, but statistically close, value than the one reported for the ferromagnetic case. The magnetic moment and atomic volume at the dislocation core differ between paramagnetic and ferromagnetic states, with possible consequences on the temperature dependence of defect-dislocation interactions.</p>","","","","","","","","","","","","","2020-10-31","2020-10-31","2020-11-16","http://liu.diva-portal.org/smash/get/diva2:1484989/FULLTEXT01.pdf","","4","","2","","","","","094420","false","","",""
"1502425","Arabi, C. Mas (Univ Libre Bruxelles, Belgium);Parra-Rivas, P. (Univ Libre Bruxelles, Belgium; Univ Leuven, Belgium);Hansson, Tobias [tobha84] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Gelens, L. (Univ Leuven, Belgium);Wabnitz, S. (Sapienza Univ Rome, Italy; CNR INO, Italy; Novosibirsk State Univ, Russia);Leo, F. (Univ Libre Bruxelles, Belgium)","Localized structures formed through domain wall locking in cavity-enhanced second-harmonic generation","Artikel i tidskrift","Refereegranskat","eng","Optics Letters","0146-9592","1539-4794","published","45","20","","5856","5859","2020","","","","OPTICAL SOC AMER","","","","","","","10.1364/OL.399658","000581198200056","33057302","","urn:nbn:se:liu:diva-171476","","","","Annan fysik (10399)","","","<p>Funding Agencies|VetenskapsradetSwedish Research Council [2017-05309]; European Research CouncilEuropean Research Council (ERC) [757800]; Fonds De La Recherche Scientifique-FNRSFonds de la Recherche Scientifique - FNRS; Ministry of Science and Higher Education of theRussian Federation [Y26.31.0017]</p>","<p>We analyze the formation of localized structures in cavity-enhanced second-harmonic generation. We focus on the phase-matched limit, and consider that fundamental and generated waves have opposite signs of group velocity dispersion. We show that these states form due to the locking of domain walls connecting two stable homogeneous states of the system, and undergo collapsed snaking. We study the impact of temporal walk-off on the stability and dynamics of these localized states. (C) 2020 Optical Society of America</p>","","","","","","","","","","","","","2020-11-19","2020-11-19","2020-11-19","","","6","","2","","","","","","false","","",""
"1485171","Kakanakova-Gueorguieva, Anelia [aneka59] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Gueorguiev, Gueorgui Kostov [guegu96] [0000-0001-9402-1491] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Sangiovanni, Davide [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Suwannaharn, Nattamon [natsu01] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Chulalongkorn Univ, Thailand);Ivanov, Ivan Gueorguiev [ivaiv28] [0000-0003-1000-0437] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Cora, Ildiko (Ctr Energy Res, Hungary);Pecz, Bela (Ctr Energy Res, Hungary);Nicotra, Giuseppe (Ist Microelettron & Microsistemi, Italy);Giannazzo, Filippo (Ist Microelettron & Microsistemi, Italy)","Nanoscale phenomena ruling deposition and intercalation of AlN at the graphene/SiC interface","Artikel i tidskrift","Refereegranskat","eng","Nanoscale","2040-3364","2040-3372","published","12","37","","19470","19476","2020","","","","ROYAL SOC CHEMISTRY","","","","","","","10.1039/d0nr04464d","000574599500044","32960193","","urn:nbn:se:liu:diva-170933","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|FLAG-ERA 2015 JTC project GRIFONE through Swedish Research Council [VR 2015-06816]; National Research Development and Innovation Office, Hungary NN [118914]; Italian Ministry of Education and Research (MIUR) under project Beyond-NanoMinistry of Education, Universities and Research (MIUR) [PON a3_00363, VR 2017-04071, AF15-557, KAW 2013.0049, AF18-266]; Swedish Research CouncilSwedish Research Council [SNIC 2020/5-146, SNIC 2020/14-17, 2018-05973]; Italian Ministry of Education and Research (MIUR) under the project EleGaNTeMinistry of Education, Universities and Research (MIUR) [PON ARS01_01007]; European Structural and Investment Funds [VEKOP-2.3.3-15-2016-00002]; [VR 2016-05362]</p>","<p>The possibility for kinetic stabilization of prospective 2D AlN was explored by rationalizing metal organic chemical vapor deposition (MOCVD) processes of AlN on epitaxial graphene. From the wide range of temperatures which can be covered in the same MOCVD reactor, the deposition was performed at the selected temperatures of 700, 900, and 1240 degrees C. The characterization of the structures by atomic force microscopy, electron microscopy and Raman spectroscopy revealed a broad range of surface nucleation and intercalation phenomena. These phenomena included the abundant formation of nucleation sites on graphene, the fragmentation of the graphene layers which accelerated with the deposition temperature, the delivery of excess precursor-derived carbon adatoms to the surface, as well as intercalation of sub-layers of aluminum atoms at the graphene/SiC interface. The conceptual understanding of these nanoscale phenomena was supported by our previous comprehensiveab initiomolecular dynamics (AIMD) simulations of the surface reaction of trimethylaluminum, (CH3)(3)Al, precursor with graphene. A case of applying trimethylindium, (CH3)(3)In, precursor to epitaxial graphene was considered in a comparative way.</p>","","","","","","","","","","","","","2020-11-01","2020-11-01","2020-11-23","http://liu.diva-portal.org/smash/get/diva2:1485171/FULLTEXT01.pdf","","9","","1","","","","","","false","","",""
"1485212","Gharavi, Mohammad Amin [mohgh20] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Armiento, Rickard [ricar47] [0000-0002-5571-0814] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Eklund, Per [perek02] [0000-0003-1785-0864] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Theoretical study of the phase transitions and electronic structure of (Zr-0.5, Mg-0.5)N and (Hf-0.5, Mg-0.5)N","Artikel i tidskrift","Refereegranskat","eng","Journal of Materials Science","0022-2461","1573-4803","aheadofprint","","","","","","2020","","","","SPRINGER","","","","","","","10.1007/s10853-020-05372-1","000574340400001","","","urn:nbn:se:liu:diva-171049","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Linkoping University</p>","<p>Rock-salt scandium nitride has gained interest due to its thermoelectric properties including a relatively high Seebeck coefficient. This motivates research for other semiconductor materials that exhibit similar electronic structure features as ScN. Using density functional theory calculations, we have studied disordered solid solutions of (Zr-0.5, Mg-0.5)N and (Hf-0.5, Mg-0.5)N using the special quasi-random structure model. The results show that within a mean-field approximation for the configurational entropy, the order-disorder phase transformation between the monoclinic LiUN(2)prototype structure and the rock-salt cubic random alloy of these mentioned solid solutions occur at 740 K and 1005 K for (Zr-0.5, Mg-0.5)N and (Hf-0.5, Mg-0.5)N, respectively. The density-of-states for the two ternary compounds is also calculated and predicts semiconducting behavior with band gaps of 0.75 eV for (Zr-0.5, Mg-0.5)N and 0.92 eV for (Hf-0.5, Mg-0.5)N. The thermoelectric properties of both compounds are also predicted. We find that in the range of a moderate change in the Fermi level, a high Seebeck coefficient value at room temperature can be achieved.</p>","","","","","","","","","","","","","2020-11-01","2020-11-01","2020-11-23","http://liu.diva-portal.org/smash/get/diva2:1485212/FULLTEXT01.pdf","","4","","1","","","","","","false","","",""
"1499263","Huang, Yuqing [yuqhu58] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Puttisong, Yuttapoom [yutpu33] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Filippov, Stanislav [stafi86] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Buyanova, Irina [iribo40] [0000-0001-7155-7103] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Chen, Weimin [weich55] [0000-0002-6405-9509] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Oblique Nuclear Quadrupole Interaction in Self-Assembled Structures Based on Semiconductor Quantum Dots","Artikel i tidskrift","Refereegranskat","eng","Physical Review Applied","","2331-7019","published","14","4","","","","2020","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevApplied.14.044019","000579524800002","","","urn:nbn:se:liu:diva-171182","","","","Annan fysik (10399)","","","<p>Funding Agencies|Linkoping University; Swedish Research CouncilSwedish Research Council [2016-05091]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]</p>","<p>Dynamic nuclear polarization (DNP) is well recognized as being important in spintronics and quantum-information processing. DNP gives rise to high nuclear spin polarization that not only can prolong electron-spin lifetime by generating an Overhauser field (OHF), but also has fertilized the idea to explore nuclear spin qubits. In strained quantum-dot structures (QDSs), a nuclear spin is coupled to a strain field via its quadrupole moment. It has been shown that such nuclear quadrupole interaction (NQI) can be used to achieve appreciable DNP and hence electron-spin polarization. Here, we uncover magneto-optical anomalies from a series of laterally arranged (In,Ga)As QDSs that arise from the NQI and DNP in these nanostructures. We find that the principal axis of NQI in symmetry-lowered QDSs significantly deviates from the growth direction, resulting in tilting of OHF with an angle exceeding 37 degrees. The resulting transverse component of OHF is probed with respect to the crystallographic orientations and its influence on the DNP and ensemble spin dephasing is analyzed. We show that a high-symmetry electronic confinement potential for excitons does not guarantee a high-symmetry NQI for nuclei within the same nano-object, thereby calling for correlated optimization in the symmetry of the electronic confinement potential and that of the nuclear spin bath. Our results underline the role of oblique NQI in electron-spin decoherence and depolarization, which has so far largely been overlooked. This work thus sheds light on design rules for engineering the electronic and spin landscape of QDSs for better performance of DNP desirable for applications in spintronics and quantum computation.</p>","","","","","","","","","","","","","2020-11-08","2020-11-08","2020-11-25","http://liu.diva-portal.org/smash/get/diva2:1499263/FULLTEXT01.pdf","","5","","1","","","","","044019","false","","",""
"1502418","Skripnyak, Natalia [natsk33] [0000-0003-1634-5882] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Tasnadi, Ferenc [ferta55] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ponomareva, A. V. (Natl Univ Sci & Technol MISIS, Russia);Lofstrand, J. (Uppsala Univ, Sweden);Berastegui, P. (Uppsala Univ, Sweden);Jansson, U. (Uppsala Univ, Sweden);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Achieving low elastic moduli of bcc Ti-V alloys in vicinity of mechanical instability","Artikel i tidskrift","Refereegranskat","eng","AIP Advances","2158-3226","2158-3226","published","10","10","","","","2020","","","","AMER INST PHYSICS","","","","","","","10.1063/5.0023347","000585818400001","","","urn:nbn:se:liu:diva-171482","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Swedish Research Council (VR)Swedish Research Council [2018-04834]; VINN Excellence Center Functional Nanoscale Materials (FunMat-2) [2016-05156]; Swedish Government Strategic Research Areas in Materials Science on Functional Materials at Linkoping University [2009-00971]; RFBRRussian Foundation for Basic Research (RFBR) [20-02-00178]</p>","<p>Body centered cubic (bcc) Ti-based alloys are of interest for multiple technological applications ranging from aerospace technology to biomedicine. However, these alloys are usually unstable at low temperatures. Indeed, the calculated elastic modulus C of bcc Ti-V alloys with low V concentrations is negative at 0 K temperature, indicating their mechanical instability. Here, we investigate elastic moduli of the Ti-V system in the vicinity of mechanical instability theoretically and experimentally. Our calculations predict that mechanical stabilization of bcc Ti-V alloys, which is governed by the hardening of C , is possible at as low V concentration as 18 at.%. We synthesize single-phase bcc alloys with as little as 22 at.% of V with low values of Youngs modulus. Moreover, we predict strong concentration dependence of anisotropy of Youngs modulus in these alloys that can also be used in tuning the alloy composition to design materials for specific applications.</p>","","","","","","","","","","","","","2020-11-19","2020-11-19","2020-12-08","http://liu.diva-portal.org/smash/get/diva2:1502418/FULLTEXT01.pdf","","8","","1","","","","","105322","false","","",""
"1502652","Shapeev, Alexander V (Skolkovo Inst Sci & Technol, Russia);Podryabinkin, Evgeny V (Skolkovo Inst Sci & Technol, Russia);Gubaev, Konstantin (Skolkovo Inst Sci & Technol, Russia);Tasnadi, Ferenc [ferta55] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (NUST MISIS, Russia)","Elinvar effect in beta-Ti simulated by on-the-fly trained moment tensor potential","Artikel i tidskrift","Refereegranskat","eng","New Journal of Physics","1367-2630","1367-2630","published","22","11","","","","2020","","","","IOP PUBLISHING LTD","","","","","","","10.1088/1367-2630/abc392","000584988800001","","","urn:nbn:se:liu:diva-171467","","","machine learning; ab initio molecular dynamics; Elinvar effect; bcc titanium","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Knut and AliceWallenberg Foundation (Wallenberg Scholar Grant) [KAW-2018.0194]; VINN Excellence Center Functional Nanoscale Materials [2016-05156]; Swedish Government Strategic Research Areas in Materials Science on Functional Materials at Linkoping University [2009-00971]; Ministry of Science and Education of the Russian Federation in the framework of the Increase Competitiveness Program of NUST MISIS [K2-2019-001, 211]; RFBRRussian Foundation for Basic Research (RFBR) [20-02-00178, 20-53-12012]</p>","<p>A combination of quantum mechanics calculations with machine learning techniques can lead to a paradigm shift in our ability to predict materials properties from first principles. Here we show that on-the-fly training of an interatomic potential described through moment tensors provides the same accuracy as state-of-the-art ab initio molecular dynamics in predicting high-temperature elastic properties of materials with two orders of magnitude less computational effort. Using the technique, we investigate high-temperature bcc phase of titanium and predict very weak, Elinvar, temperature dependence of its elastic moduli, similar to the behavior of the so-called GUM Ti-based alloys (Sato et al 2003 Science 300 464). Given the fact that GUM alloys have complex chemical compositions and operate at room temperature, Elinvar properties of elemental bcc-Ti observed in the wide temperature interval 1100-1700 K is unique.</p>","","","","","","","","","","","","","2020-11-20","2020-11-20","2020-12-08","http://liu.diva-portal.org/smash/get/diva2:1502652/FULLTEXT01.pdf","","5","","1","","","","","113005","false","","",""
"1466446","Bakhit, Babak [babba34] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Palisaitis, Justinas [juspa01] [0000-0003-3203-7935] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Persson, Per O.Å. [perpe25] [0000-0001-9140-6724] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Rosen, Johanna [johro07] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Hultman, Lars [larhu75] [0000-0002-2837-3656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Petrov, Ivan [ivape26] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Materials Research Laboratory and Department of Materials Science, University of Illinois, Urbana IL 61801, USA; Department of Materials Science and Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan);Greene, Joseph E [josgr17] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Materials Research Laboratory and Department of Materials Science, University of Illinois, Urbana IL 61801, USA; Department of Materials Science and Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan);Greczynski, Grzegorz [grzgr49] [0000-0002-4898-5115] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Self-organized columnar Zr0.7Ta0.3B1.5 core/shell-nanostructure thin films","Artikel i tidskrift","Refereegranskat","eng","Surface & Coatings Technology","0257-8972","1879-3347","published","401","","","","","2020","","","","Elsevier","","","","","","","10.1016/j.surfcoat.2020.126237","000583161500008","","2-s2.0-85089079938","urn:nbn:se:liu:diva-169201","","","Thin films;Transition-metal (TM) diborides;Self-organized;Core/shell nanostructure;Hardness and toughness","Fysik (103)","","","<p>Funding agencies: Knut and Alice Wallenberg (KAW) FoundationKnut & Alice Wallenberg Foundation [KAW 2015.0043]; electron microscopy laboratory in Linkoping; Swedish Research Council VRSwedish Research Council [2014-5790, 2018-03957, 2019-05403, 642-2013-8020]; VINNOVA Gran</p>","<p data-select-like-a-boss=""1"">We recently showed that Zr1−xTaxBy thin films have columnar nanostructure in which column boundaries are B-rich for x < 0.2, while Ta-rich for x ≥ 0.2. Layers with x ≥ 0.2 exhibit higher hardness and, simultaneously, enhanced toughness. Here, we determine the atomic-scale nanostructure of sputter-deposited columnar Zr0.7Ta0.3B1.5 thin films. The columns, 95 ± 17 Å, are core/shell nanostructures in which 80 ± 15-Å cores are crystalline hexagonal-AlB2-structure Zr-rich stoichiometric Zr1−xTaxB2. The shell structure is a narrow dense, disordered region that is Ta-rich and highly B-deficient. The cores are formed under intense ion mixing via preferential Ta segregation, due to the lower formation enthalpy of TaB2 than ZrB2, in response to the chemical driving force to form a stoichiometric compound. The films with unique combination of nanosized crystalline cores and dense metallic-glass-like shells provide excellent mechanical properties.</p>","","","","","","","","","","","","","2020-09-11","2020-09-11","2020-12-09","http://liu.diva-portal.org/smash/get/diva2:1466446/FULLTEXT01.pdf","","9","","1","urn:nbn:se:liu:diva-171848","","","","126237","true","","",""
"1459903","Gordeeva, Alisa (Stockholm Univ, Sweden);Hsu, Ying-Jui (Umea Univ, Sweden);Jenei, Istvan Z. (Stockholm Univ, Sweden);Carvalho, Paulo H. B. Brant (Stockholm Univ, Sweden);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Andersson, Ove (Umea Univ, Sweden);Haussermann, Ulrich (Stockholm Univ, Sweden)","Layered Zinc Hydroxide Dihydrate, Zn-5(OH)(10)center dot 2H(2)O, from Hydrothermal Conversion of epsilon-Zn(OH)(2) at Gigapascal Pressures and its Transformation to Nanocrystalline ZnO","Artikel i tidskrift","Refereegranskat","eng","ACS Omega","","2470-1343","published","5","28","","17617","17627","2020","","","","AMER CHEMICAL SOC","","","","","","","10.1021/acsomega.0c02075","000554991800064","32715247","","urn:nbn:se:liu:diva-168279","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|Swedish Research Council (VR)Swedish Research Council [2016-04413, 2019-05551]; Stiftelsen Olle Engkvist Byggmastare (SOEB); Swedish Foundation for Strategic Research (SSF) within the Swedish National Graduate School in neutron scattering (SwedNess); Swedish Government Strategic Research Area Grant in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]</p>","<p>Layered zinc hydroxides (LZHs) with the general formula (Zn2+)(x)(OH-)(2x-my ),(A(m-))(y)center dot nH(2)O (A(m-) = Cl- , NO3- , ac(-) , SO42-, etc) are considered as useful precursors for the fabrication of functional ZnO nanostructures. Here, we report the synthesis and structure characterization of the hitherto unknown ""binary"" representative of the LZH compound family, Zn-5(OH)(10)center dot 2H(2)O, with A(m-) = OH- , x = 5, y = 2, and n = 2. Zn-5(OH)(10)center dot 2H(2)O was afforded quantitatively by pressurizing mixtures of epsilon-Zn(OH)(2) (wulfingite) and water to 1-2 GPa and applying slightly elevated temperatures, 100-200 degrees C. The monoclinic crystal structure was characterized from powder X-ray diffraction data (space group C2/c, a = 15.342(7) angstrom, b = 6.244(6) angstrom, c = 10.989(7) angstrom, beta = 100.86(1)degrees). It features neutral zinc hydroxide layers, composed of octahedrally and tetrahedrally coordinated Zn ions with a 3:2 ratio, in which H2O is intercalated. The interlayer d(200) distance is 7.53 angstrom. The H-bond structure of Zn-5(OH)(10)center dot 2H(2)O was analyzed by a combination of infrared/Raman spectroscopy, computational modeling, and neutron powder diffraction. Interlayer H2O molecules are strongly H-bonded to five surrounding OH groups and appear orientationally disordered. The decomposition of Zn-5(OH)(10)center dot 2H(2)O, which occurs thermally between 70 and 100 degrees C, was followed in an in situ transmission electron microscopy study and ex situ annealing experiments. It yields initially 5-15 nm sized hexagonal w-ZnO crystals, which, depending on the conditions, may intergrow to several hundred nm-large two-dimensional, flakelike crystals within the boundary of original Zn-5(OH)(10)center dot 2H(2)O particles.</p>","","","","","","","","","","","","","2020-08-21","2020-08-21","2020-12-15","http://liu.diva-portal.org/smash/get/diva2:1459903/FULLTEXT01.pdf","","7","","1","","","","","","false","","",""
"1434919","Spektor, Kristina (ESRF, France);Crichton, Wilson A. (ESRF, France);Filippov, Stanislav [stafi86] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Stockholm Univ, Sweden);Klarbring, Johan [johkl85] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Fischer, Andreas (Augsburg Univ, Germany);Haussermann, Ulrich (Stockholm Univ, Sweden)","Na-Ni-H Phase Formation at High Pressures and High Temperatures: Hydrido Complexes [NiH5](3-) Versus the Perovskite NaNiH3","Artikel i tidskrift","Refereegranskat","eng","ACS Omega","","2470-1343","published","5","15","","8730","8743","2020","","","","AMER CHEMICAL SOC","","","","","","","10.1021/acsomega.0c00239","000527748400067","32337435","","urn:nbn:se:liu:diva-165956","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|Swedish Research Council (VR)Swedish Research Council [2019-05551]; Swedish Government Strategic Research Area in Materials Science on Advanced Functional Materials at at Linkoping University (Faculty Grant SFO-Mat-LiU) [200900971]; Carl Tryggers Stiftelse (CTS) [16:198, 17:206]</p>","<p>The Na-Ni-H system was investigated by in situ synchrotron diffraction studies of reaction mixtures NaH-Ni-H-2 at around 5, 10, and 12 GPa. The existence of ternary hydrogen-rich hydrides with compositions Na3NiH5 and NaNiH3, where Ni attains the oxidation state II, is demonstrated. Upon heating at similar to 5 GPa, face-centered cubic (fcc) Na3NiH5 forms above 430 degrees C. Upon cooling, it undergoes a rapid and reversible phase transition at 330 degrees C to an orthorhombic (Cmcm) form. Upon pressure release, Na3NiH5 further transforms into its recoverable Pnma form whose structure was elucidated from synchrotron powder diffraction data, aided by first-principles density functional theory (DFT) calculations. Na3NiH5 features previously unknown square pyramidal 18- electron complexes NiH53-. In the high temperature fcc form, metal atoms are arranged as in the Heusler structure, and ab initio molecular dynamics simulations suggest that the complexes are dynamically disordered. The Heusler-type metal partial structure is essentially maintained in the low temperature Cmcm form, in which NiH53- complexes are ordered. It is considerably rearranged in the low pressure Pnma form. Experiments at 10 GPa showed an initial formation of fcc Na3NiH5 followed by the addition of the perovskite hydride NaNiH3, in which Ni(II) attains an octahedral environment by H atoms. NaNiH3 is recoverable at ambient pressures and represents the sole product of 12 GPa experiments. DFT calculations show that the decomposition of Na3NiH5 = NaNiH3 + 2 NaH is enthalpically favored at all pressures, suggesting that Na3NiH5 is metastable and its formation is kinetically favored. Ni-H bonding in metallic NaNiH3 is considered covalent, as in electron precise Na3NiH5, but delocalized in the polyanion [NiH3](-).</p>","","","","","","","","","","","","","2020-06-04","2020-06-04","2020-12-15","http://liu.diva-portal.org/smash/get/diva2:1434919/FULLTEXT01.pdf","","7","","1","","","","","","false","","",""
"1423118","Sangiovanni, Davide [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Ruhr Univ Bochum, Germany);Tasnadi, Ferenc [ferta55] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Johnson, L. J. S. (Sandvik Coromant, Sweden);Odén, Magnus [magod41] [0000-0002-2286-5588] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Nanostrukturerade material [2221]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Strength, transformation toughening, and fracture dynamics of rocksalt-structure Ti1-xAlxN (0 <= x <= 0.75) alloys","Artikel i tidskrift","Refereegranskat","eng","Physical Review Materials","","2475-9953","published","4","3","","","","2020","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevMaterials.4.033605","000521132400002","","","urn:nbn:se:liu:diva-165053","","","","Fysik (103)","","","<p>Funding Agencies|Competence Center Functional Nanoscale Materials (FunMat-II) (Vinnova Grant)Vinnova [2016-05156]; Swedish Research Council (VR)Swedish Research Council [2019-05600]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; Knut and AliceWallenberg Foundation throughWallenberg Scholar project [2018.0194]; Olle Engkvist Foundation</p>","<p>Ab initio-calculated ideal strength and toughness describe the upper limits for mechanical properties attainable in real systems and can, therefore, be used in selection criteria for materials design. We employ density-functional ab initio molecular dynamics (AIMD) to investigate the mechanical properties of defect-free rocksalt-structure (B1) TiN and B1 Ti1-xAlxN (x = 0.25, 0.5, 0.75) solid solutions subject to [001], [110], and [111] tensile deformation at room temperature. We determine the alloys ideal strength and toughness, elastic responses, and ability to plastically deform up to fracture as a function of the Al content. Overall, TiN exhibits greater ideal moduli of resilience and tensile strengths than (Ti,Al)N solid solutions. Nevertheless, AIMD modeling shows that, irrespective of the strain direction, the binary compound systematically fractures by brittle cleavage at its yield point. The simulations also indicate that Ti0.5Al0.5N and Ti0.25Al0.75N solid solutions are inherently more resistant to fracture and possess much greater toughness than TiN due to the activation of local structural transformations (primarily of B1 -amp;gt; wurtzite type) beyond the elastic-response regime. In sharp contrast, (Ti,Al)N alloys with 25% Al exhibit similar brittleness as TiN. The results of this work are examples of the limitations of elasticity-based criteria for prediction of strength, brittleness, ductility, and toughness in materials able to undergo phase transitions with loading. Comparing present and previous findings, we suggest a general principle for design of hard ceramic solid solutions that are thermodynamically inclined to dissipate extreme mechanical stresses via transformation toughening mechanisms.</p>","","","","","","","","","","","","","2020-04-14","2020-04-14","2020-12-15","http://liu.diva-portal.org/smash/get/diva2:1423118/FULLTEXT01.pdf","","5","","1","","","","","033605","false","","",""
"1394203","Ponomareva, A. V. (Natl Univ Sci and Technol MISIS, Russia);Mukhamedov, B. O. (Natl Univ Sci and Technol MISIS, Russia; Natl Univ Sci and Technol MISIS, Russia);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia)","Theoretical modeling of interstitial carbon impurities in paramagnetic Fe-Mn alloys","Artikel i tidskrift","Refereegranskat","eng","Physical Review Materials","","2475-9953","published","4","2","","","","2020","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevMaterials.4.024401","000510845400002","","","urn:nbn:se:liu:diva-163653","","","","Metallurgi och metalliska material (20506)","","","<p>Funding Agencies|Russian Science FoundationRussian Science Foundation (RSF) [18-12-00492]; Swedish Research Council (VR)Swedish Research Council [2015-04391]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]</p>","<p>We present a generalization of a model that takes into account the magnetic disorder of paramagnetic host with interstitial point defects towards the case of alloy hosts. In the framework of disordered local moment approach combined with magnetic sampling method, we calculate solution enthalpy of carbon impurity in the paramagnetic fcc Fe-Mn steels. First, we use the magnetic special quasirandom structure (M-SQS) method for simulation of the paramagnetic state in Fe-Mn alloys without impurity. Here, Fe and Mn atoms are randomly distributed at the sites of a supercell following the chemical SQS method. Next, to calculate the energies for various magnetic realizations around the interstitial carbon impurity, we vary the position of the impurity within the SQS. Our calculations show that in alloys containing similar to 20 at. % Mn, the solution enthalpy of carbon reduces compared to the pure fcc-Fe. By analyzing the local and global effects of impurity on the properties of the matrix, we discuss various factors that could increase the carbon solubility in high-manganese austenitic steels.</p>","","","","","","","","","","","","","2020-02-18","2020-02-18","2020-12-15","http://liu.diva-portal.org/smash/get/diva2:1394203/FULLTEXT01.pdf","","3","","1","","","","","024401","false","","",""
"1393725","Smirnova, Daria (Ruhr Univ Bochum, Germany);Starikov, Sergei (Ruhr Univ Bochum, Germany);Leines, Grisell Diaz (Ruhr Univ Bochum, Germany);Liang, Yanyan (Ruhr Univ Bochum, Germany);Wang, Ning (Ruhr Univ Bochum, Germany);Popov, Maxim N. (Mat Ctr Leoben Forsch GmbH, Austria);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Sangiovanni, Davide [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Ruhr Univ Bochum, Germany);Drautz, Ralf (Ruhr Univ Bochum, Germany);Mrovec, Matous (Ruhr Univ Bochum, Germany)","Atomistic description of self-diffusion in molybdenum: A comparative theoretical study of non-Arrhenius behavior","Artikel i tidskrift","Refereegranskat","eng","Physical Review Materials","","2475-9953","published","4","1","","","","2020","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevMaterials.4.013605","000507548000001","","","urn:nbn:se:liu:diva-163450","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|scope of the COMET program within the K2 Center ""Integrated Computational Material, Process and Product Engineering (IC-MPPE)"" [859480]; Austrian Federal Ministry for Transport, Innovation, and Technology (BMVIT); Austrian Federal Ministry for Digital and Economic Affairs (BMDW); federal state of Styria; federal state of Upper Austria; federal state of Tyrol; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFOMat-LiU) [2009-00971]; VINN Excellence Center Functional Nanoscale Materials (FunMat-2) Grant [2016-05156]; German Research Foundation (DFG)German Research Foundation (DFG) [RO 3073/6-1]; Mexican National Council for Science and Technology (CONACYT)Consejo Nacional de Ciencia y Tecnologia (CONACyT) [232090]; Olle Engkvist Foundation</p>","<p>According to experimental observations, the temperature dependence of self-diffusion coefficient in most body-centered cubic metals (bcc) exhibits non-Arrhenius behavior. The origin of this behavior is likely related to anharmonic vibrational effects at elevated temperatures. However, it is still debated whether anharmonicity affects more the formation or migration of monovacancies, which are known to govern the self-diffusion. In this extensive atomistic simulation study we investigated thermodynamic properties of monovacancies in bcc molybdenum, here taken as a representative model system, from zero temperature to the melting point. We combined first-principles calculations and classical simulations based on three widely used interatomic potentials for Mo. In our analysis we employ static and dynamic atomistic calculations as well as statistical sampling techniques and thermodynamic integration to achieve thorough information about temperature variations of vacancy formation and migration free energies and diffusivities. In addition, we carry out large-scale molecular dynamics simulations that enable direct observation of high-temperature self-diffusion at the atomic scale. By scrutinizing the results obtained by different models and methods, we conclude that the peculiar self-diffusion behavior is likely caused by strong temperature dependence of the vacancy formation energy.</p>","","","","","","","","","","","","","2020-02-17","2020-02-17","2020-12-15","","","10","","1","","","","","013605","false","","",""
"1514676","Bugaev, K. A. (Bogolyubov Inst Theoret Phys, Ukraine; Taras Shevchenko Natl Univ Kyiv, Ukraine);Ivanytskyi, O. I. (Bogolyubov Inst Theoret Phys, Ukraine; Univ Coimbra, Portugal);Grinyuk, B. E. (Bogolyubov Inst Theoret Phys, Ukraine);Yakymenko, Iryna [iryya88] [0000-0001-6635-3130] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","BOSE-EINSTEIN CONDENSATION AS A DEPOSITION PHASE TRANSITION OF QUANTUM HARD SPHERES AND NEW RELATIONS BETWEEN BOSONIC AND FERMIONIC PRESSURES","Artikel i tidskrift","Refereegranskat","eng","UKRAINIAN JOURNAL OF PHYSICS","2071-0186","","published","65","11","","963","972","2020","","","","BOGOLYUBOV INST THEORETICAL PHYSICS NATL ACAD SCI UKRAINE","","","","","","","10.15407/ujpe65.11.963","000590871000003","","","urn:nbn:se:liu:diva-172340","","","quantum gases; Van der Waals; equation of state; statistical multifragmentation model; Bose-Einstein condensation; deposition phase transition","Annan fysik (10399)","","","<p>Funding Agencies|Program of Fundamental Research in High Energy and Nuclear Physics; COST Action ""THOR""European Cooperation in Science and Technology (COST) [CA15213]</p>","<p>We investigate the phase transition of Bose-Einstein particles with the hard-core repulsion in the grand canonical ensemble within the Van der Waals approximation. It is shown that the pressure of non-relativistic Bose-Einstein particles is mathematically equivalent to the pressure of simplified version of the statistical multifragmentation model of nuclei with the vanishing surface tension coefficient and the Fisher exponent tau(F) = 5/2, which for such parameters has the 1-st order phase transition. The found similarity of these equations of state allows us to show that within the present approach the high density phase of Bose-Einstein particles is a classical macro-cluster with vanishing entropy at any temperature which, similarly to the system of classical hard spheres, is a kind of solid state. To show this we establish new relations which allow us to identically represent the pressure of Fermi-Dirac particles in terms of pressures of Bose-Einstein particles of two sorts.</p>","","","","","","","","","","","","","2021-01-07","2021-01-07","2021-01-07","","","4","","0","","","","","","false","","",""
"1512941","Hamdi, Hanen (Wigner Res Ctr Phys, Hungary);Thiering, Gergo (Wigner Res Ctr Phys, Hungary);Bodrog, Zoltan (Wigner Res Ctr Phys, Hungary);Ivády, Viktor [vikiv58] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Wigner Res Ctr Phys, Hungary);Gali, Adam (Wigner Res Ctr Phys, Hungary; Budapest Univ Technol & Econ, Hungary)","Stone-Wales defects in hexagonal boron nitride as ultraviolet emitters","Artikel i tidskrift","Refereegranskat","eng","NPJ Computational Materials","2057-3960","","published","6","1","","","","2020","","","","Nature Research","","","","","","","10.1038/s41524-020-00451-y","000596014300001","","","urn:nbn:se:liu:diva-172193","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|National Research, Development and Innovation Office in Hungary for Quantum Technology Program [2017-1.2.1-NKP-2017-00001]; National Excellence Program [KKP129866]; Ministry of Innovation and Technology; National Research, Development and Innovation Office within the Quantum Information National Laboratory of Hungary; European Commission for the EU H2020 Asteriqs project [820394]; MTA Premium Postdoctoral Research Program; Knut and Alice Wallenberg Foundation through WBSQD2 project [2018.0071]; Janos Bolyai Research Scholarship of the Hungarian Academy of SciencesHungarian Academy of Sciences; New National Excellence Program for Ministry Innovation and Technology from the source of the National Research, Development and Innovation Fund [UNKP-20-5]</p>","<p>Many quantum emitters have been measured close or near the grain boundaries of the two-dimensional hexagonal boron nitride where various Stone-Wales defects appear. We show by means of first principles density functional theory calculations that the pentagon-heptagon Stone-Wales defect is an ultraviolet emitter and its optical properties closely follow the characteristics of a 4.08-eV quantum emitter, often observed in polycrystalline hexagonal boron nitride. We also show that the square-octagon Stone-Wales line defects are optically active in the ultraviolet region with varying gaps depending on their density in hexagonal boron nitride. Our results may introduce a paradigm shift in the identification of fluorescent centres in this material.</p>","","","","","","","","","","","","","2020-12-28","2020-12-28","2021-01-22","http://liu.diva-portal.org/smash/get/diva2:1512941/FULLTEXT01.pdf","","5","","0","","","","","178","false","","",""
"1515010","Johansson, Erik [erijo40] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ektarawong, Annop (Chulalongkorn Univ, Thailand; Minist Higher Educ Sci Res & Innovat, Thailand);Rosén, Johanna [johro07] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Theoretical investigation of mixing and clustering thermodynamics of Ti1-xAlxB2 alloys with potential for age-hardening","Artikel i tidskrift","Refereegranskat","eng","Journal of Applied Physics","0021-8979","1089-7550","published","128","23","","","","2020","","","","AMER INST PHYSICS","","","","","","","10.1063/5.0030927","000599771400001","","","urn:nbn:se:liu:diva-172310","","","","Metallurgi och metalliska material (20506)","","","<p>Funding Agencies|Knut and Alice Wallenberg (KAW) FoundationKnut & Alice Wallenberg Foundation [KAW 2015.0043]; Swedish Research Council (VR)Swedish Research Council [2014-6336, 2019-05403]; Marie Sklodowska Curie Actions [INCA 600398]; Knut and Alice Wallenberg Foundation (Wallenberg Scholar Grant) [KAW-2018.0194]; Swedish Foundation for Strategic Research through the Future Research Leaders 6 program [FFL 15-0290]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; Thailand Toray Science Foundation (TTSF); Ratchadaphiseksomphot Endowment Fund, Chulalongkorn University and Grants for Research [CU-GR_62_66_23_26]</p>","<p>Metastable ternary ceramic alloys with clustering tendencies are candidates for hard coating applications. In this work, mixing thermodynamics and structural parameters of ceramic Ti1-xAlxB2 alloys are investigated with theoretical first-principles based techniques. Lattice dynamics and temperature dependent phase stability are explored. The effect of lattice vibrations on the total free energy is investigated and found to not significantly affect phase stability at temperatures below 1200K. The isostructural phase diagram is derived using both cluster expansion-based Monte Carlo simulations and a mean field approach. The phase diagram shows a miscibility gap that does not close at temperatures below the melting or decomposition temperatures of the constituent binaries TiB2 and AlB2. The lattice mismatch between phases in the system is small regardless of their composition even at elevated temperatures. These findings support the prospect of age hardening due to coherent isostructural decomposition, such as spinodal decomposition, in coatings of Ti(1-x)AlxB(2) as diffusion is activated at elevated temperature. (c) 2020 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).</p>","","","","","","","","","","","","","2021-01-07","2021-01-07","2021-01-26","http://liu.diva-portal.org/smash/get/diva2:1515010/FULLTEXT01.pdf","","4","","1","","","","","235101","false","","",""
"1501276","Gervilla, Víctor [vicge54] [0000-0003-2759-4147] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Nanodesign [16854]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Zarshenas, Mohammad [mohza46] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Nanodesign [16854]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Sangiovanni, Davide Giuseppe [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Sarakinos, Kostas [kossa66] [0000-0003-2864-9509] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Nanodesign [16854]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Anomalous versus Normal Room-Temperature Diffusion of Metal Adatoms on Graphene","Artikel i tidskrift","Refereegranskat","eng","Journal of Physical Chemistry Letters","1948-7185","1948-7185","published","11","21","","8930","8936","2020","","","Washington, DC, United States","American Chemical Society","","","","","","","10.1021/acs.jpclett.0c02375","000589920000001","32986445","2-s2.0-85095799468","urn:nbn:se:liu:diva-171416","","","","Fysikalisk kemi (10402)","","","<p>Funding agencies: Swedish research council (contract VR-2015-04630), ÅForsk foundation (contract ÅF 19-137), Olle Engkvist foundation (contract SOEB 190-312), Swedish Research Council through Grant Agreement No. VR-2015-04630</p><p></p>","<p>Fabrication of high-performance heterostructure devices requires fundamental understanding of the diffusion dynamics of metal species on 2D materials. Here, we investigate the room-temperature diffusion of Ag, Au, Cu, Pd, Pt, and Ru adatoms on graphene using ab initio and classical molecular dynamics simulations. We find that Ag, Au, Cu, and Pd follow Lévy walks, in which adatoms move continuously within ∼1–4 nm2 domains during ∼0.04 ns timeframes, and they occasionally perform ∼2–4 nm flights across multiple surface adsorption sites. This anomalous diffusion pattern is associated with a flat (<50 meV) potential energy landscape (PEL), which renders surface vibrations important for adatom migration. The latter is not the case for Pt and Ru, which encounter a significantly rougher PEL (>100 meV) and, hence, migrate via conventional random walks. Thus, adatom anomalous diffusion is a potentially important aspect for modeling growth of metal films and nanostructures on 2D materials.</p>","","","","","","","","","","","","","2020-11-16","2020-11-16","2021-01-31","http://liu.diva-portal.org/smash/get/diva2:1501276/FULLTEXT01.pdf","","4","","1","urn:nbn:se:liu:diva-171435","","","","","true","true","",""
"1435202","Davidsson, Joel [joeda01] [0000-0002-5349-3318] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ivády, Viktor [vikiv58] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Hungarian Acad Sci, Hungary);Armiento, Rickard [ricar47] [0000-0002-5571-0814] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ohshima, Takeshi (Natl Inst Quantum and Radiol Sci and Technol, Japan);Nguyen, Son Tien [nguso90] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Gali, Adam (Hungarian Acad Sci, Hungary; Budapest Univ Technol and Econ, Hungary);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia)","Correction: Identification of divacancy and silicon vacancy qubits in 6H-SiC (vol 114, 112107, 2019)","Artikel i tidskrift","Refereegranskat","eng","Applied Physics Letters","0003-6951","1077-3118","published","116","5","","","","2020","","","","AMER INST PHYSICS","","","","","http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-156202","","10.1063/1.5144728","000513133500004","","","urn:nbn:se:liu:diva-165974","","","","Fysik (103);Kemi (104)","","","","<p>n/a</p>","","","","","","","","","","","","","2020-06-04","2020-06-04","2021-02-08","http://liu.diva-portal.org/smash/get/diva2:1435202/FULLTEXT01.pdf","","7","","2","urn:nbn:se:liu:diva-173108","","","","059901","false","","",""
"1521650","Casillas Trujillo, Luis [luica08] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Jansson, Ulf (Uppsala Univ, Sweden);Sahlberg, Martin (Uppsala Univ, Sweden);Ek, Gustav (Uppsala Univ, Sweden);Nygard, Magnus M. (Inst Energy Technol, Norway);Sorby, Magnus H. (Inst Energy Technol, Norway);Hauback, Bjorn C. (Inst Energy Technol, Norway);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci & Technol MISIS, Russia);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Interstitial carbon in bcc HfNbTiVZr high-entropy alloy from first principles","Artikel i tidskrift","Refereegranskat","eng","Physical Review Materials","","2475-9953","published","4","12","","","","2020","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevMaterials.4.123601","000598179100002","","","urn:nbn:se:liu:diva-172613","","","","Teoretisk kemi (10407)","","","<p>Funding Agencies|Swedish Research Council (VR)Swedish Research Council [2019-05403, 2018-04834]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University, Faculty Grant SFOMatLiU [2009 00971]; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation [KAW2018.0194]; Swedish Foundation for Strategic Research through the Future Research Leaders 6 program [FFL 15-0290]; RFBRRussian Foundation for Basic Research (RFBR) [20-02-00178]; NordForsk Nordic Neutron Science Programme through the functional hydrides (FunHy) project [81942]</p>","<p>The remarkable mechanical properties of high-entropy alloys can be further improved by interstitial alloying. In this work we employ density functional theory calculations to study the solution energies of dilute carbon interstitial atoms in tetrahedral and octahedral sites in bcc HfNbTiVZr. Our results indicate that carbon interstitials in tetrahedral sites are unstable, and the preferred octahedral sites present a large spread in the energy of solution. The inclusion of carbon interstitials induces large structural relaxations with long-range effects. The effect of local chemical environment on the energy of solution is investigated by performing a local cluster expansion including studies of its correlation with the carbon atomic Voronoi volume. However, the spread in solution energetics cannot be explained with a local environment analysis only pointing towards a complex, long-range influence of interstitial carbon in this alloy.</p>","","","","","","","","","","","","","2021-01-24","2021-01-24","2021-02-09","http://liu.diva-portal.org/smash/get/diva2:1521650/FULLTEXT01.pdf","","9","","1","","","","","123601","false","","",""
"1524155","Spektor, Kristina (European Synchrotron Radiat Facil, France);Crichton, Wilson A. (European Synchrotron Radiat Facil, France);Filippov, Stanislav [stafi86] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Stockholm Univ, Sweden);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Fischer, Andreas (Augsburg Univ, Germany);Haussermann, Ulrich (Stockholm Univ, Sweden)","Na3FeH7 and Na3CoH6: Hydrogen-Rich First-Row Transition Metal Hydrides from High Pressure Synthesis","Artikel i tidskrift","Refereegranskat","eng","Inorganic Chemistry","0020-1669","1520-510X","published","59","22","","16467","16473","2020","","","","AMER CHEMICAL SOC","","","","","","","10.1021/acs.inorgchem.0c02294","000592794400036","33141575","","urn:nbn:se:liu:diva-173079","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|Swedish Government Strategic Research Area Grant in Materials Science on Functional Materials at Linkoping University [2009 00971]; Carl Tryggers Stiftelse (CTS) [16:198, 17:206]</p>","<p>The formation of ternary hydrogen-rich hydrides involving the first-row transition metals TM = Fe and Co in high oxidation states is demonstrated from in situ synchrotron diffraction studies of reaction mixtures NaH-TM-H-2 at p approximate to 10 GPa. Na3FeH7 and Na3CoH6 feature pentagonal bipyramidal FeH73- and octahedral CoH63- 18-electron complexes, respectively. At high pressure, high temperature (300 &lt; T &lt;= 470 degrees C) conditions, metal atoms are arranged as in the face-centered cubic Heusler structure, and ab initio molecular dynamics simulations suggest that the complexes undergo reorientational dynamics. Upon cooling, subtle changes in the diffraction patterns evidence reversible and rapid phase transitions associated with ordering of the complexes. During decompression, Na3FeH7 and Na3CoH6 transform to tetragonal and orthorhombic low pressure forms, respectively, which can be retained at ambient pressure. The discovery of Na3FeH7 and Na3CoH6 establishes a consecutive series of homoleptic hydrogen-rich complexes for first-row transition metals from Cr to Ni.</p>","","","","","","","","","","","","","2021-01-31","2021-01-31","2021-02-19","http://liu.diva-portal.org/smash/get/diva2:1524155/FULLTEXT01.pdf","","6","","2","","","","","","false","","",""
"1515706","Davidsson, Joel [joeda01] [0000-0002-5349-3318] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Theoretical polarization of zero phonon lines in point defects","Artikel i tidskrift","Refereegranskat","eng","Journal of Physics: Condensed Matter","0953-8984","1361-648X","published","32","38","","","","2020","","","","Institute of Physics Publishing","","","","","","","10.1088/1361-648X/ab94f4","000615675400001","","2-s2.0-85087110345","urn:nbn:se:liu:diva-172513","","","density functional theory;photoluminescence;Point defects;zero phonon line;Excited states;Phonons;Polarization;Silicon carbide;Wave functions;Wide band gap semiconductors;Defects in semiconductors;Divacancies;Quantum technologies;Radiative lifetime;Zero phonon lines","Den kondenserade materiens fysik (10304)","","","","<p>In quantum technologies, point defects in semiconductors are becoming more significant. Understanding the frequency, intensity, and polarization of the zero phonon line is important. The last two properties are the subject of this paper. I present a method for calculating these properties and show the importance of using wave functions from both the ground and excited state. The validity of this method is demonstrated on the divacancy in 4H-SiC. Here, the calculated polarization and radiative lifetimes are in excellent agreement with experimental measurements. In general, this method can help to identify point defects and estimate suitable applications.</p>","","","","","","","","","","","","","2021-01-11","2021-01-11","2021-02-21","http://liu.diva-portal.org/smash/get/diva2:1515706/FULLTEXT01.pdf","","1","","1","urn:nbn:se:liu:diva-173108","","","","385502","false","true","",""
"1529947","Errandonea, Daniel (Univ Valencia, Spain);Burakovsky, Leonid (Los Alamos Natl Lab, NM 87545 USA);Preston, Dean L. (Los Alamos Natl Lab, NM 87545 USA);MacLeod, Simon G. (Univ Edinburgh, Scotland; AWE, England);Santamaria-Perez, David (Univ Valencia, Spain);Chen, Shaoping (Los Alamos Natl Lab, NM 87545 USA);Cynn, Hyunchae (Lawrence Livermore Natl Lab, CA 94551 USA);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);McMahon, Malcolm I. (Univ Edinburgh, Scotland);Proctor, John E. (Univ Edinburgh, Scotland);Mezouar, Mohamed (European Synchrotron Radiat Facil, France)","Experimental and theoretical confirmation of an orthorhombic phase transition in niobium at high pressure and temperature","Artikel i tidskrift","Refereegranskat","eng","COMMUNICATIONS MATERIALS","2662-4443","","published","1","1","","","","2020","","","","Springer Nature","","","","","","","10.1038/s43246-020-00058-2","000610560700003","","","urn:nbn:se:liu:diva-173436","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Spanish Ministerio de Ciencia, Innovacion y Universidades [MAT2016-75586-C4-1-P, PGC2018-097520-A-100, RED2018-102612-T]; Generalitat ValencianaGeneralitat Valenciana [Prometeo/2018/123 EFIMAT]; Spanish governmentSpanish Government [RyC-2014-15643]; US Department of EnergyUnited States Department of Energy (DOE) [DE-AC52-07NA27344]</p>","<p>Compared to other body-centered cubic (bcc) transition metals, Nb has been the subject of fewer compression studies and there are still aspects of its phase diagram which are unclear. Here, we report a combined theoretical and experimental study of Nb under high pressure and temperature. We present the results of static laser-heated diamond anvil cell experiments up to 120 GPa using synchrotron-based fast x-ray diffraction combined with ab initio quantum molecular dynamics simulations. The melting curve of Nb is determined and evidence for a solid-solid phase transformation in Nb with increasing temperature is found. The high-temperature phase of Nb is orthorhombic Pnma. The bcc-Pnma transition is clearly seen in the experimental data on the Nb principal Hugoniot. The bcc-Pnma coexistence observed in our experiments is explained. Agreement between the measured and calculated melting curves is very good except at 40-60 GPa where three experimental points lie below the theoretical melting curve by 250 K (or 7%); a possible explanation is given. The study of materials under extreme conditions can reveal interesting physics in diverse areas such as condensed matter and geophysics. Here, the authors investigate experimentally and theoretically the high pressure-high temperature phase diagram of niobium revealing a previously unobserved phase transition from body-centered cubic to orthorhombic phase.</p>","","","","","","","","","","","","","2021-02-20","2021-02-20","2021-03-09","http://liu.diva-portal.org/smash/get/diva2:1529947/FULLTEXT01.pdf","","11","","1","","","","","60","false","","",""
"1454940","Ji, Fuxiang [fuxji90] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Klarbring, Johan [johkl85] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Wang, Feng [fenwa69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ning, Weihua [weini20] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Wang, Linqin (KTH Royal Inst Technol, Sweden);Yin, Chunyang [chuyi94] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Mendoza Figueroa, José Silvestre [josme81] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biofysik och bioteknik [883402]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Christensen, Christian Kolle (DESY, Germany);Etter, Martin (DESY, Germany);Ederth, Thomas [thoed88] [0000-0002-1639-5735] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biofysik och bioteknik [883402]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Sun, Licheng (KTH Royal Inst Technol, Sweden; Dalian Univ Technol, Peoples R China);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia);Gao, Feng [fenga88] [0000-0002-2582-1740] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Lead-Free Halide Double Perovskite Cs(2)AgBiBr(6)with Decreased Band Gap","Artikel i tidskrift","Refereegranskat","eng","Angewandte Chemie International Edition","1433-7851","1521-3773","aheadofprint","","","","","","2020","","","","WILEY-V C H VERLAG GMBH","","","","","","","10.1002/anie.202005568","000542143400001","32412132","","urn:nbn:se:liu:diva-167742","","","Ag-Bi disorder; band-gap engineering; crystal engineering; Cs2AgBiBr6; lead-free double perovskites","Teoretisk kemi (10407)","","","<p>Funding Agencies|Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation; Swedish Energy AgencySwedish Energy Agency [2018-004357]; VR Starting Grant [2019-05279]; Carl Tryggers Stiftelse; Olle Engkvist Byggmastare Stiftelse; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; Swedish Energy AgencySwedish Energy Agency; SSFSwedish Foundation for Strategic Research; China Scholarship Council (CSC)China Scholarship Council; Ministry of Science and High Education of the Russian Federation [075-15-2019-872 (14.Y26.31.0027/074-02-2018-327)]; Swedish Research Council (VR)Swedish Research Council [2019-05551]; Swedish Research CouncilSwedish Research Council [2016-07213]</p>","<p>Environmentally friendly halide double perovskites with improved stability are regarded as a promising alternative to lead halide perovskites. The benchmark double perovskite, Cs2AgBiBr6, shows attractive optical and electronic features, making it promising for high-efficiency optoelectronic devices. However, the large band gap limits its further applications, especially for photovoltaics. Herein, we develop a novel crystal-engineering strategy to significantly decrease the band gap by approximately 0.26 eV, reaching the smallest reported band gap of 1.72 eV for Cs(2)AgBiBr(6)under ambient conditions. The band-gap narrowing is confirmed by both absorption and photoluminescence measurements. Our first-principles calculations indicate that enhanced Ag-Bi disorder has a large impact on the band structure and decreases the band gap, providing a possible explanation of the observed band-gap narrowing effect. This work provides new insights for achieving lead-free double perovskites with suitable band gaps for optoelectronic applications.</p>","","","","","","","","","","","","","2020-07-21","2020-07-21","2021-03-20","http://liu.diva-portal.org/smash/get/diva2:1454940/FULLTEXT01.pdf","","14","","2","","","","","","false","","",""
"1538953","Gambino, Davide [davga91] [0000-0002-7763-7224] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Brännvall, Marian [marbr60] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ehn, Amanda [amaeh38] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Hedström, Ylva [ylvhe40] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Longitudinal spin fluctuations in bcc and liquid Fe at high temperature and pressure calculated with a supercell approach","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","102","1","","","","2020","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.102.014402","000544842300002","","","urn:nbn:se:liu:diva-174528","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Swedish Research Council (VR) through International Career GrantSwedish Research Council [2014-6336, 2019-05403]; Marie Sklodowska Curie Actions [INCA 600398]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; Knut and Alice Wallenberg Foundation (Wallenberg Scholar Grant) [KAW-2018.0194]; Swedish Foundation for Strategic Research through the Future Research Leaders 6 program [FFL 15-0290]</p>","<p>Investigating magnetic materials at realistic conditions with first-principles methods is a challenging task due to the interplay of vibrational and magnetic degrees of freedom. The most difficult contribution to include in simulations is represented by the longitudinal magnetic degrees of freedom [longitudinal spin fluctuation (LSF)] due to their inherent many-body nature; nonetheless, schemes that enable to take into account this effect on a semiclassical level have been proposed and employed in the investigation of magnetic systems. However, assessment of the effect of vibrations on LSF is lacking in the literature. For this reason, in this work we develop a supercell approach within the framework of constrained density functional theory to calculate self-consistently the size of local-environment-dependent magnetic moments in the paramagnetic, high-temperature state in the presence of lattice vibrations and for liquid Fe in different conditions. First, we consider the case of bcc Fe at the Curie temperature and ambient pressure. Then, we perform a similar analysis on bcc Fe at Earths inner-core conditions, and we find that LSFs stabilize nonzero moments which affect atomic forces and the electronic density of states of the system. Finally, we employ the present scheme on liquid Fe at the melting point at ambient pressure and at Earths outer-core conditions (p approximate to 200 GPa, T approximate to 6000 K). In both cases, we obtain local magnetic moments of sizes comparable to the solid-state counterparts.</p>","","","","","","","","","","","","","2021-03-22","2021-03-22","2021-03-22","http://liu.diva-portal.org/smash/get/diva2:1538953/FULLTEXT01.pdf","","5","","2","","","","","014402","true","true","",""
"1274658","Mosyagin, Igor [igomo87] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (NUST MISTS, Russia);Lugovskoy, A. V. (NUST MISTS, Russia);Krasilnikov, O. M. (NUST MISTS, Russia; NUST MISTS, Russia);Vekilov, Yu. Kh. (NUST MISTS, Russia; NUST MISTS, Russia);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Reply to the comment by M. Mazdziarz on the article ""Ab initio calculations of pressure-dependence of high-order elastic constants using finite deformations approach"" [Computer Physics Communications 220 (2017) 20-30]","Artikel i tidskrift","Övrigt vetenskapligt","eng","Computer Physics Communications","0010-4655","1879-2944","published","235","","","295","296","2019","","","","ELSEVIER SCIENCE BV","","","","","","","10.1016/j.cpc.2018.06.007","000451491100028","","","urn:nbn:se:liu:diva-153493","","","Ab initio calculations; Elastic moduli; Pressure effects in solids and liquids; Finite deformations","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Swedish Research Council [2015-04391, 2014-4750]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; Ministry of Education and Science of the Russian Federation [K2-2017-080, 14.Y26.31.0005]</p>","<p>Marcin Mazdziarz has published a comment on our recent paper by I. Mosyagin, A.V. Lugovskoy, O.M. Krasilnikov, Yu.Kh. Vekilov, S.I. Simak and L.A. Abrikosov titled ""Ab initio calculations of pressure dependence of high-order elastic constants using finite deformations approach"" [Computer Physics Communications 220 (2017)2030]. The author states that there are serious fundamental errors and flaws. In this reply we clarify all misunderstanding mentioned in the said comment. (C) 2018 Published by Elsevier B.V.</p>","","","","","","","","","","","","","2019-01-02","2019-01-02","2019-03-25","","","6","","1","","editorialMaterial","","","","false","","",""
"1318766","Pakornchote, T. (Chulalongkorn Univ, Thailand; Thailand Ctr Excellence Phys, Thailand);Ektarawong, Annop [annek02] [0000-0002-6059-6833] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Max Planck Inst Eisenforsch GmbH, Germany);Pinsook, U. (Chulalongkorn Univ, Thailand; Thailand Ctr Excellence Phys, Thailand);Tancharakorn, S. (Synchrotron Light Res Inst Publ Org, Thailand);Busayaporn, W. (Synchrotron Light Res Inst Publ Org, Thailand);Bovornratanaraks, T. (Chulalongkorn Univ, Thailand; Thailand Ctr Excellence Phys, Thailand)","Phase stabilities and vibrational analysis of hydrogenated diamondized bilayer graphenes: A first principles investigation","Artikel i tidskrift","Refereegranskat","eng","Carbon","0008-6223","1873-3891","published","146","","","468","475","2019","","","","PERGAMON-ELSEVIER SCIENCE LTD","","","","","","","10.1016/j.carbon.2019.01.088","000465408900051","","","urn:nbn:se:liu:diva-156908","","","Diamondized bilayer graphene; 2-Dimensional materials; Vibrational analysis","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Royal Golden Jubilee (RGJ) program; 90th Chulalongkorn Scholarship; Chulalongkorn University; Ratchadaphiseksomphot Endowment Fund of Chulalongkorn University; Kungl. Ingenjorsvetenskapsakademiens Hans Werthen-Fond; Swedish Research Council [2014-6336]; Marie Sklodowska Curie Actions [INCA 600398]; Swedish Foundation for Strategic Research through the Future Research Leaders 6 program; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]; Sci-SuperIV research grant, Faculty of Science</p>","<p>The phase stabilities as well as some intrinsic properties of hydrogenated diamondized bilayer graphenes, 2-dimensional materials adopting the crystal structure of diamond and of lonsdaleite, are investigated using a first-principles approach. Our simulations demonstrate that hydrogenated diamondized bilayer graphenes are thermodynamically stable with respect to bilayer graphene and hydrogen molecule even at 0 GPa, and additionally they are found to withstand the physical change in structure up to at least 1000 K, ensuring their dynamical and thermal stabilities. The studied hydrogenated diamondized bilayer graphenes are predicted not only to behave as direct and wide band gap semiconductors, but also to have a remarkably high resistance to in-plane plastic deformation induced by indentation as implied by their high in-plane elastic constants comparable to those of diamond and of lonsdaleite. The mechanical stability of the materials is confirmed though the fulfilment of the Born stability criteria. Detailed analysis of phonon vibrational frequencies of hydrogenated diamondized bilayer graphenes reveals possible Raman active and IR active modes, which are found to be distinctly different from those of hydrogenated diamond-like amorphous carbon and defective graphene and thus could be used as a fingerprint for future experimental characterization of the materials. (c) 2019 Elsevier Ltd. All rights reserved.</p>","","","","","","","","","","","","","2019-05-28","2019-05-28","2019-05-28","","","7","","2","","","","","","false","","",""
"1324393","Parra-Rivas, Pedro (Univ Libre Bruxelles, Belgium; Univ Leuven, Belgium);Gelens, Lendert (Univ Leuven, Belgium);Hansson, Tobias [tobha84] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Wabnitz, Stefan (Sapienza Univ Rome, Italy; CNR, Italy);Leo, Francois (Univ Libre Bruxelles, Belgium)","Frequency comb generation through the locking of domain walls in doubly resonant dispersive optical parametric oscillators","Artikel i tidskrift","Refereegranskat","eng","Optics Letters","0146-9592","1539-4794","published","44","8","","2004","2007","2019","","","","OPTICAL SOC AMER","","","","","","","10.1364/OL.44.002004","000464601900031","30985796","","urn:nbn:se:liu:diva-157213","","","","Atom- och molekylfysik och optik (10302)","","","<p>Funding Agencies|Ministero dellIstruzione, dellUniversita e della Ricerca (MIUR) [2015KEZNYM]; Vetenskapsradet (VR) [2017-05309]; H2020 European Research Council (ERC) [757800]; KU Leuven; Fonds De La Recherche Scientifique-FNRS (FNRS)</p>","<p>In this Letter we theoretically investigate the formation of localized temporal dissipative structures, and their corresponding frequency combs in doubly resonant dispersive optical parametric oscillators. We derive a nonlocal mean field model, and show that domain wall locking allows for the formation of stable coherent optical frequency combs. (C) 2019 Optical Society of America</p>","","","","","","","","","","","","","2019-06-13","2019-06-13","2019-06-13","","","5","","2","","","","","","false","","",""
"1297808","de Sousa, Leonardo Evaristo (Univ Brasilia, Brazil);Bueno, Fernando Teixeira (Univ Brasilia, Brazil);da Silva Filho, Demetrio Antonio (Univ Brasilia, Brazil);Ribeiro, Luiz Antonio [luiri41] [0000-0001-7468-2946] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Brasilia, Brazil);de Oliveira Neto, Pedro Henrique (Univ Brasilia, Brazil)","Dynamical exciton decay in organic materials: the role of bimolecular recombination","Artikel i tidskrift","Refereegranskat","eng","Physical Chemistry, Chemical Physics - PCCP","1463-9076","1463-9084","published","21","4","","1711","1716","2019","","","","ROYAL SOC CHEMISTRY","","","","","","","10.1039/c8cp05951a","000459584100004","30620347","","urn:nbn:se:liu:diva-155599","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior - Brasil (CAPES) [001]; Brazilian Research Council CNPq; Brazilian Research Council FAPDF [0193.001.511/2017, 0193.001662/2017]; Brazilian Ministry of Planning, Budget and Management [DIPLA 005/2016]; CNPq [304020/2016-8, 407682/2013-9]; FAP-DF [193.001.596/2017, 193.001.284/2016]; CENAPAD-SP</p>","<p>Excitons play a critical role in light emission when it comes to organic semiconductors. In high exciton concentration regimes, monomolecular and bimolecular routes for exciton recombination can yield different products affecting significantly the materials optical properties. Here, the dynamical decay of excitons is theoretically investigated using a kinetic Monte Carlo approach that addresses singlet exciton diffusion. Our numerical protocol includes two distinct exciton-exciton interaction channels: exciton annihilation and biexciton cascade emission. Our findings reveal that these channels produce different consequences concerning diffusion and spectroscopic properties, being able to explain diverging experimental observations. Importantly, we estimate critical exciton densities for which bimolecular recombination becomes dominant and investigate its effect on average exciton lifetimes and diffusion lengths.</p>","","","","","","","","","","","","","2019-03-21","2019-03-21","2019-06-27","","","5","","2","","","","","","false","","",""
"1302130","Pereira Junior, Marcelo Lopes (Univ Brasilia, Brazil);de Sousa Junior, Rafael Timoteo (Univ Brasilia, Brazil);Magela e Silva, Geraldo (Univ Brasilia, Brazil);Ribeiro, Luiz Antonio [luiri41] [0000-0001-7468-2946] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Brasilia, Brazil)","Stationary polaron properties in organic crystalline semiconductors","Artikel i tidskrift","Refereegranskat","eng","Physical Chemistry, Chemical Physics - PCCP","1463-9076","1463-9084","published","21","5","","2727","2733","2019","","","","ROYAL SOC CHEMISTRY","","","","","","","10.1039/c8cp06915h","000461667900052","30664136","","urn:nbn:se:liu:diva-156106","","","","Annan fysik (10399)","","","<p>Funding Agencies|CNPq; CAPES; FAP-DF; CENAPAD-SP; Brazilian Ministry of Planning, Development and Management [005/2016 DIPLA, 11/2016 SEST]; DPGU - Brazilian Union [066/2016]; FAP-DF [0193.001. 511/2017, 0193.001766/2017]</p>","<p>Polarons play a crucial role in the charge transport mechanism when it comes to organic molecular crystals. The features of their underlying properties - mostly the ones that directly impact the yield of the net charge mobility - are still not completely understood. Here, a two-dimensional Holstein-Peierls model is employed to numerically describe the stationary polaron properties in organic semiconductors at a molecular scale. Our computational protocol yields model parameters that accurately characterize the formation and stability of polarons in ordered and disordered oligoacene-like crystals. The results show that the interplay between the intramolecular (Holstein) and intermolecular (Peierls) electron-lattice interactions critically impacts the polaron stability. Such an interplay can produce four distinct quasi-particle solutions: free-like electrons, metastable polarons, and small and large polarons. The latter governs the charge transport in organic crystalline semiconductors. Regarding disordered lattices, the model takes into account two modes of static disorder. Interestingly, the results show that intramolecular disorder is always unfavorable to the formation of polarons whereas intermolecular disorder may favor the polaron generation in regimes below a threshold for the electronic transfer integral strength.</p>","","","","","","","","","","","","","2019-04-03","2019-04-03","2019-06-27","","","4","","2","","","","","","false","","",""
"1281564","da Cunha, Wiliam Ferreira (Univ Brasilia, Brazil);de Oliveira Neto, Pedro Henrique (Univ Brasilia, Brazil);Ribeiro, Luiz Antonio [luiri41] [0000-0001-7468-2946] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Brasilia, Brazil);Magela e Silva, Geraldo (Univ Brasilia, Brazil)","Quasiparticle description of transition metal dichalcogenide nanoribbons","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","99","3","","","","2019","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.99.035405","000454766400013","","","urn:nbn:se:liu:diva-153960","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|CNPq; Brazilian Ministry of Planning, Development and Management [005/2016 DIPLA]; FAP-DF [0193.001766/2017, 0193.001511/2017, 0193.001662/2017, 0193.001694/2017]</p>","<p>An effective two-dimensional real-space model is developed to investigate the nature of charge distribution in nanoribbons of transition metal dichalcogenides. Our description is based on a lattice relaxation endowed tight-binding Hamiltonian with spin-orbit and Hubbard interactions, which is parameterized to describe molybdenum disulfide lattices. As our main finding, we observed that electron-phonon coupling induces the creation of quasiparticles such as polarons in the same fashion as observed in conducting polymers and graphene nanoribbons. These similarities suggest that the charge transport in transition metal dichalcogenides can also be mediated by quasiparticles, which is a fundamental aspect concerning the application of these structures in electronics. We determine a range of possible electron-phonon coupling that correctly describes the system and also the critical value where quasiparticle transport is present. Our findings may have profound consequences on the understanding of the transport mechanism of transition metal dichalcogenides nanoribbons.</p>","","","","","","","","","","","","","2019-01-22","2019-01-22","2019-06-27","","","4","","2","","","","","035405","false","","",""
"1297803","Almyras, Georgios [geoal24] [0000-0002-2541-2867] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Nanodesign [16854]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Sangiovanni, Davide Giuseppe [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Ruhr Univ Bochum, Germany);Sarakinos, Kostas [kossa66] [0000-0003-2864-9509] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Nanodesign [16854]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Semi-Empirical Force-Field Model For The Ti<sub>1-X</sub>Al<sub>X</sub>N (0 ≤ x ≤ 1) System","Artikel i tidskrift","Refereegranskat","eng","Materials","1996-1944","1996-1944","published","12","2","","","","2019","","","","MDPI","","","","","","","10.3390/ma12020215","000459719000019","30634593","","urn:nbn:se:liu:diva-155607","","","titanium-aluminum nitride; Ti-Al-N; MD simulations; molecular dynamics; interatomic potential; MEAM; force-field model; spinodal decomposition; phase stability","Metallurgi och metalliska material (20506)","","","<p>Funding Agencies|Olle Engkvist foundation; competence center FunMat-II - Vinnova [2016-05156]; Linkoping University (""LiU Career Contract"") [LiU-2015-01510]; Swedish research council [VR-2015-04630]; Olle Engkvist foundation [SOEB 190-312]</p>","<p>We present a modified embedded atom method (MEAM) semi-empirical force-field model for the Ti1-xAlxN (0 x 1) alloy system. The MEAM parameters, determined via an adaptive simulated-annealing (ASA) minimization scheme, optimize the models predictions with respect to 0 K equilibrium volumes, elastic constants, cohesive energies, enthalpies of mixing, and point-defect formation energies, for a set of approximate to 40 elemental, binary, and ternary Ti-Al-N structures and configurations. Subsequently, the reliability of the model is thoroughly verified against known finite-temperature thermodynamic and kinetic properties of key binary Ti-N and Al-N phases, as well as properties of Ti1-xAlxN (0 amp;lt; x amp;lt; 1) alloys. The successful outcome of the validation underscores the transferability of our model, opening the way for large-scale molecular dynamics simulations of, e.g., phase evolution, interfacial processes, and mechanical response in Ti-Al-N-based alloys, superlattices, and nanostructures.</p>","","","","","","","","","","","","","2019-03-21","2019-03-21","2019-06-28","http://liu.diva-portal.org/smash/get/diva2:1297803/FULLTEXT01.pdf","","3","","1","","","","","215","false","","",""
"1313989","Pilemalm, Robert [robpi36] [0000-0001-5670-7644] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Pourovskii, Leonid (Centre de Physique Théorique, Ecole Polytechnique, CNRS, Université Paris-Saclay, Route de Saclay, FR-91128 Palaiseau, France / Collège de France, 11 place Marcelin Berthelot, FR-75005 Paris, France);Mosyagin, Igor (Materials Modeling and Development Laboratory, NUST “MISIS”, RU-119991 Moscow, Russia);Simak, Sergei [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Eklund, Per [perek02] [0000-0003-1785-0864] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Thermodynamic Stability, Thermoelectric, Elastic and Electronic Structure Properties of ScMN<sub>2</sub>-Type (M = V, Nb, Ta) Phases Studied by ab initio Calculations","Artikel i tidskrift","Refereegranskat","eng","Condensed Matter","2410-3896","","published","4","2","","","","2019","","","Basel","MDPI","","","","","","","10.3390/condmat4020036","000475286700002","","","urn:nbn:se:liu:diva-156671","","","ScTaN2; inverse MAX phase; thermoelectric properties; density functional theory","Fysik (103);Den kondenserade materiens fysik (10304)","","","<p>Funding agencies: Swedish Research Council (VR) [2016-03365]; Knut and AliceWallenberg Foundation through the Academy Fellows Program; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; European Res</p>","<p>ScMN<sub>2</sub>-type (M = V, Nb, Ta) phases are layered materials that have been experimentally reported for M = Ta and Nb, but they have up to now not been much studied. However, based on the properties of binary ScN and its alloys, it is reasonable to expect these phases to be of relevance in a range of applications, including thermoelectrics. Here, we have used first-principles calculations to study their thermodynamic stability, elastic, thermoelectric and electronic properties. We have used density functional theory to calculate lattice parameters, the mixing enthalpy of formation and electronic density of states as well as the thermoelectric properties and elastic constants (c<sub>ij</sub>), bulk (B), shear (G) and Young’s (E) modulus, which were compared with available experimental data. Our results indicate that the considered systems are thermodynamically and elastically stable and that all are semiconductors with small band gaps. All three materials display anisotropic thermoelectric properties and indicate the possibility to tune these properties by doping. In particular, ScVN<sub>2</sub>, featuring the largest band gap exhibits a particularly large and strongly doping-sensitive Seebeck coefficient.</p>","","","","","","","","","","","","","2019-05-07","2019-05-07","2019-07-30","http://liu.diva-portal.org/smash/get/diva2:1313989/FULLTEXT01.pdf","","5","","1","urn:nbn:se:liu:diva-155101","","","","36","true","true","",""
"1292651","Tal, Alexey A. (Ecole Polytech Fed Lausanne, Switzerland);Posada-Borbon, Alvaro (Chalmers Univ Technol, Sweden; Chalmers Univ Technol, Sweden);Gronbeck, Henrik J. (Chalmers Univ Technol, Sweden; Chalmers Univ Technol, Sweden);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia)","Correlation between Ethylene Adsorption Energies and Core-Level Shifts for Pd Nanoclusters","Artikel i tidskrift","Refereegranskat","eng","The Journal of Physical Chemistry C","1932-7447","1932-7455","published","123","4","","2544","2548","2019","","","","AMER CHEMICAL SOC","","","","","","","10.1021/acs.jpcc.8b10465","000457816600055","","","urn:nbn:se:liu:diva-154685","","","","Teoretisk kemi (10407)","","","<p>Funding Agencies|Knut and Alice Wallenberg Foundation [2012.0083]; Strong Field Physics and New States of Matter 2014-2019 (COTXS); Ministry of Education and Science of the Russian Federation [K2-2019-001, 211]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; Knut and Alice Wallenberg Foundation through the project Atomistic design of catalysts [2015.0058]</p>","<p>Density functional theory calculations have been used to investigate the adsorption of ethylene on Pd nanoclusters together with shifts in core-level binding energies of Pd atoms bonded to the adsorbate. The adsorption energy is found to correlate with the core-level shifts (CLS), which is consistent with the notion that the core-level binding energy is a measure of differences in cohesion. The correlation between adsorption energies and core-level shifts is found to be stronger than the correlation between adsorption energies and generalized coordination numbers, indicating that descriptors preferably should account for electronic effects explicitly. The advantages of CLS as a descriptor for the screening of adsorption properties is discussed.</p>","","","","","","","","","","","","","2019-02-28","2019-02-28","2019-07-31","","","4","","1","","","","","","false","","",""
"1315885","Ektarawong, Annop [annek02] [0000-0002-6059-6833] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Singapore, Singapore);Peng, Y. P. (Natl Univ Singapore, Singapore);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Phase stability of three-dimensional bulk and two-dimensional monolayer As1-xSbx solid solutions from first principles","Artikel i tidskrift","Refereegranskat","eng","Journal of Physics: Condensed Matter","0953-8984","1361-648X","published","31","24","","","","2019","","","","IOP PUBLISHING LTD","","","","","","","10.1088/1361-648X/ab0fd2","000463199400002","30870814","","urn:nbn:se:liu:diva-156548","","","bulk/multilayer As1-xSbx; monolayer As1-xSbx; phase diagram; mixing thermodyanmics; first-principles approach; cluster-expansion formalism; density functional theory","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Swedish Research Council (VR) [2014-6336]; Marie Sklodowska Curie Actions, Cofund [INCA 600398]; Swedish Foundation for Strategic Research (SSF); Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; Kungl. Ingenjorsvetenskapsakademiens Hans Werthen-Fond</p>","<p>The mixing thermodynamics of both three-dimensional bulk and two-dimensional monolayered alloys of As1-xSbx as a function of alloy composition and temperature are explored using a first-principles cluster-expansion method, combined with canonical Monte-Carlo simulations. We observe that, for the bulk phase, As1-xSbx alloy can exhibit not only chemical ordering of As and Sb atoms at x = 0.5 to form an ordered compound of AsSb stable upon annealing up to T approximate to 475 K, but also a miscibility gap at 475 K less than or similar to T less than or similar to 550 K in which two disordered solid solutions of As1-xSbx of different alloy compositions thermodynamically coexist. At T amp;gt; 550 K, a single-phase solid solution of bulk As1-xSbx is predicted to be stable across the entire composition range. These results clearly explain the existing uncertainties in the alloying behavior of bulk As1-xSbx alloy, as previously reported in the literature, and also found to be in qualitative and quantitative agreement with the experimental observations. Interestingly, the alloying behavior of As1-xSbx is considerably altered, as the dimensionality of the material reduces from the three-dimensional bulk state to the two-dimensional monolayered state-for example, a single-phase solid solution of monolayer As1-xSbx is predicted to be stable over the whole composition range at T amp;gt; 250 K. This distinctly highlights an influence of the reduced dimensionality on the alloying behavior of As1-xSbx.</p>","","","","","","","","","","","","","2019-05-15","2019-05-15","2019-08-13","http://liu.diva-portal.org/smash/get/diva2:1315885/FULLTEXT01.pdf","","3","","1","","","","","245702","false","","",""
"1338415","Palonen, H. (Uppsala Univ, Sweden);Mukhamedov, B. O. (Natl Univ Sci and Technol MISIS, Russia);Ponomareva, A. V. (Natl Univ Sci and Technol MISIS, Russia);Palsson, G. K. (Uppsala Univ, Sweden);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Hjorvarsson, B. (Uppsala Univ, Sweden)","The magnetization profile induced by the double magnetic proximity effect in an Fe/Fe0.30V0.70 superlattice","Artikel i tidskrift","Refereegranskat","eng","Applied Physics Letters","0003-6951","1077-3118","published","115","1","","","","2019","","","","AMER INST PHYSICS","","","","","","","10.1063/1.5102121","000474211400020","","","urn:nbn:se:liu:diva-159063","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Swedish Research Council; Ministry of Science and High Education of the Russian Federation in the framework of Increase Competitiveness Program of NUST (MISIS) [K2-2019-001, 211]; Swedish Government Strategic Research Areas in Materials Science on Functional Materials at Linkoping University [2009-00971]; Swedish e-Science Centre</p>","<p>The double magnetic proximity effect (MPE) in an Fe/Fe0.30V0.70 superlattice is studied by a direct measurement of the magnetization profile using polarized neutron reflectivity. The experimental magnetization profile is shown to qualitatively agree with a profile calculated using density functional theory. The profile is divided into a short range interfacial part and a long range tail. The interfacial part is explained by charge transfer and induced magnetization, while the tail is attributed to the inhomogeneous nature of the FeV alloy. The long range tail in the magnetization persists up to 170% above the intrinsic ordering temperature of the FeV alloy. The observed effects can be used to design systems with a direct exchange coupling between layers over long distances through a network of connected atoms. When combined with the recent advances in tuning and switching, the MPE with electric fields and currents, the results can be applied in spintronic devices. Published under license by AIP Publishing.</p>","","","","","","","","","","","","","2019-07-22","2019-07-22","2019-08-15","http://liu.diva-portal.org/smash/get/diva2:1338415/FULLTEXT01.pdf","","6","","2","","","","","012406","false","","",""
"1338419","Bykov, Maxim (Univ Bayreuth, Germany);Chariton, Stella (Univ Bayreuth, Germany);Fei, Hongzhan (Univ Bayreuth, Germany);Fedotenko, Timofey (Univ Bayreuth, Germany);Aprilis, Georgios (Univ Bayreuth, Germany);Ponomareva, Alena V (Natl Univ Sci and Technol MISIS, Russia);Tasnadi, Ferenc [ferta55] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Merle, Benoit (Friedrich Alexander Univ Erlangen Nurnberg FAU, Germany);Feldners, Patrick (Friedrich Alexander Univ Erlangen Nurnberg FAU, Germany);Vogel, Sebastian (Univ Munich LMU, Germany);Schnick, Wolfgang (Univ Munich LMU, Germany);Prakapenka, Vitali B. (Univ Chicago, IL 60637 USA);Greenberg, Eran (Univ Chicago, IL 60637 USA);Hanfland, Michael (European Synchrotron Radiat Facil, France);Pakhomova, Anna (DESY, Germany);Liermann, Hanns-Peter (DESY, Germany);Katsura, Tomoo (Univ Bayreuth, Germany);Dubrovinskaia, Natalia (Univ Bayreuth, Germany);Dubrovinsky, Leonid (Univ Bayreuth, Germany)","High-pressure synthesis of ultraincompressible hard rhenium nitride pernitride Re-2(N-2)(N)(2) stable at ambient conditions","Artikel i tidskrift","Refereegranskat","eng","Nature Communications","2041-1723","2041-1723","published","10","","","","","2019","","","","NATURE PUBLISHING GROUP","","","","","","","10.1038/s41467-019-10995-3","000474241100003","31278267","","urn:nbn:se:liu:diva-159058","","","","Organisk kemi (10405)","","","<p>Funding Agencies|Deutsche Forschungsgemeinschaft (DFG) [ME 4368/7-1]; Federal Ministry of Education and Research, Germany (BMBF) [5K16WC1]; Fonds der Chemischen Industrie (FCI), Germany; National Science Foundation-Earth Sciences [EAR-1634415]; Department of EnergyGeoSciences [DE-FG02-94ER14466]; DOE Office of Science by Argonne National Laboratory [DE-AC02-06CH11357]; Russian Science Foundation [18-12-00492]; Ministry of Science and High Education of the Russian Federation in the framework of Increase Competitiveness Program of NUST ""MISIS"" [K2-2019-001, 211]; Swedish Research Council (VR) [2015-04391]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkcping University [2009-00971]; VINN Excellence Center Functional Nanoscale Materials [FunMat-2, 2016-05156]; European Research Council (ERC) [787527]</p>","<p>High-pressure synthesis in diamond anvil cells can yield unique compounds with advanced properties, but often they are either unrecoverable at ambient conditions or produced in quantity insufficient for properties characterization. Here we report the synthesis of metallic, ultraincompressible (K-0 = 428(10) GPa), and very hard (nanoindentation hardness 36.7(8) GPa) rhenium nitride pernitride Re-2(N-2)(N)(2). Unlike known transition metals pernitrides Re-2(N-2)(N)(2) contains both pernitride N-2(4-) and discrete N3- anions, which explains its exceptional properties. Re-2(N-2)(N)(2) can be obtained via a reaction between rhenium and nitrogen in a diamond anvil cell at pressures from 40 to 90 GPa and is recoverable at ambient conditions. We develop a route to scale up its synthesis through a reaction between rhenium and ammonium azide, NH4N3, in a large-volume press at 33 GPa. Although metallic bonding is typically seen incompatible with intrinsic hardness, Re-2(N-2)(N)(2) turned to be at a threshold for superhard materials.</p>","","","","","","","","","","","","","2019-07-22","2019-07-22","2019-08-20","http://liu.diva-portal.org/smash/get/diva2:1338419/FULLTEXT01.pdf","","20","","2","","","","","2994","false","","",""
"1353528","Spektor, Kristina (ESRF, France);Crichton, Wilson A. (ESRF, France);Filippov, Stanislav [stafi86] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Stockholm Univ, Sweden);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Haussermann, Ulrich (Stockholm Univ, Sweden)","Exploring the Mg-Cr-H System at High Pressure and Temperature via in Situ Synchrotron Diffraction","Artikel i tidskrift","Refereegranskat","eng","Inorganic Chemistry","0020-1669","1520-510X","published","58","16","","11043","11050","2019","","","","AMER CHEMICAL SOC","","","","","","","10.1021/acs.inorgchem.9b01569","000482173300069","31364366","","urn:nbn:se:liu:diva-160429","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|Swedish Government Strategic Research Area Grant in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [200900971]; Carl Tryggers Stiftelse (CTS) for Vetenskaplig Forskning [16:198, 17:206]</p>","<p>The complex transition metal hydride Mg3CrH8 has been previously synthesized using high pressure conditions. It contains the first group 6 homoleptic hydrido complex, [Cr(II)H-7](5-). Here, we investigated the formation of Mg3CrH8 by in situ studies of reaction mixtures of 3MgH(2)-Cr-H-2 at 5 GPa. The formation of the known orthorhombic form (o-Mg3CrH8) was noticed at temperatures above 635 degrees C, albeit at a relatively slow rate. At temperatures around 750 degrees C a high temperature phase formed rapidly, which upon slow cooling converted into o-Mg3CrH8. The phase transition at high pressures occurred reversibly at similar to 735 degrees C upon heating and at similar to 675 degrees C upon slow cooling. Upon rapid cooling, a monoclinic polymorph (m-Mg3CrH8) was afforded which could be subsequently recovered and analyzed at ambient pressure. m-Mg3CrH8 was found to crystallize in P2(1)/n space group (a = 5.128 angstrom, b = 16.482 angstrom, c = 4.805 angstrom, beta = 90.27 degrees). Its structure elucidation from high resolution synchrotron powder diffraction data was aided by first-principles DFT calculations. Like the orthorhombic polymorph, m-Mg3CrH8 contains pentagonal bipyramidal complexes [CrH7](5-) and interstitial H-. The arrangement of metal atoms and interstitial H- resembles closely that of the high pressure orthorhombic form of Mg3MnH7. This suggests similar principles of formation and stabilization of hydrido complexes at high pressure and temperature conditions in the Mg-Cr-H and Mg-Mn-H systems. Calculated enthalpy versus pressure relations predict o-Mg3CrH8 being more stable than m-Mg3CrH8 by 6.5 kJ/mol at ambient pressure and by 13 kJ/mol at 5 GPa. The electronic structure of m-Mg3CrH8 is very similar to that of o-Mg3CrH8. The stable 18-electron complex [CrH7](5-) is mirrored in the occupied states, and calculated band gaps are around 1.5 eV.</p>","","","","","","","","","","","","","2019-09-23","2019-09-23","2019-09-23","","","5","","2","","","","","","false","","",""
"1334934","Yakymenko, Ivan (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Yakymenko, Irina I. [iryya88] [0000-0001-6635-3130] (Linköpings universitet [276], Tekniska fakulteten [872902]) (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]);Berggren, Karl-Fredrik [karbe79] [0000-0002-7133-6201] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Basic modelling of effects of geometry and magnetic field for quantum wires injecting electrons into a two-dimensional electron reservoir","Artikel i tidskrift","Refereegranskat","eng","Journal of Physics: Condensed Matter","0953-8984","1361-648X","published","31","34","","","","2019","","","","Institute of Physics (IOP)","","","","","","","10.1088/1361-648X/ab2206","000470758900002","31096197","","urn:nbn:se:liu:diva-158530","","","quantum wire; magnetic electron focusing; electron transport; semiconductor heterostructure; two-dimensional electron gas","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Carl Trygger Science Foundation, Stockholm project [CTS 17:506]</p>","<p>High-mobility two-dimensional electron gas (2DEG) which resides at the interface between GaAs and AlGaAs layered semiconductors has been used experimentally and theoretically to study ballistic electron transport. The present paper is motivated by recent experiments in magnetic electron focusing. The proposed device consists of two quantum point contacts (QPCs) serving as electron injector and collector which are placed in the same semiconductor GaAs/AlGaAs heterostructure. Here we focus on a theoretical study of the injection of electrons via a quantum wire/QPC into an open two-dimensional (2D) reservoir. The transport is considered for non-interacting electrons at different transmission regimes using the mode-matching technique. The proposed mode-matching technique has been implemented numerically. Electron flow through the quantum wire with hard-wall rectangular, conical and rounded openings has been studied. We have found for these three cases that the geometry of the opening does not play a crucial role for the electron propagation. When a perpendicular magnetic field is applied the electron paths in the 2D reservoir are curved. We analyse this case both classically and quantum-mechanically. The effect of spin-splitting due to exchange interactions on the electron flow is also considered. The effect is clearly present for realistic choices of device parameters and consistent with observations. The results of this study may be applied in designing magnetic focusing devices and spin separation.</p>","","","","","","","","","","","","","2019-07-03","2019-07-03","2019-09-24","","","3","","1","","","","","345302","true","","",""
"1299375","Silva, Gesiel Gomes (Goias Fed Inst Educ Sci and Technol, Brazil);Ribeiro, Luiz Antonio [luiri41] [0000-0001-7468-2946] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Brasilia, Brazil; Univ Brasilia, Brazil);Pereira Junior, Marcelo Lopes (Univ Brasilia, Brazil);de Almeida Fonseca, Antonio Luciano (Univ Brasilia, Brazil; Univ Brasilia, Brazil);de Sousa Junior, Rafael Timoteo (Univ Brasilia, Brazil);Magela e Silva, Geraldo (Univ Brasilia, Brazil)","Bipolaron Dynamics in Graphene Nanoribbons","Artikel i tidskrift","Refereegranskat","eng","Scientific Reports","2045-2322","2045-2322","published","9","","","","","2019","","","","NATURE PUBLISHING GROUP","","","","","","","10.1038/s41598-019-39774-2","000459799800058","30814607","","urn:nbn:se:liu:diva-155570","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|CNPq; CAPES; FAP-DF; CENAPAD-SP; Brazilian Ministry of Planning, Development and Management [005/2016, 11/2016]; DPGU - Brazilian Union Public Defender [066/2016]; FAP-DF grants [0193.001.511/2017, 0193.001343/2016, 0193.001766/2017]</p>","<p>Graphene nanoribbons (GNRs) are two-dimensional structures with a rich variety of electronic properties that derive from their semiconducting band gaps. In these materials, charge transport can occur via a hopping process mediated by carriers formed by self-interacting states between the excess charge and local lattice deformations. Here, we use a two-dimensional tight-binding approach to reveal the formation of bipolarons in GNRs. Our results show that the formed bipolarons are dynamically stable even for high electric field strengths when it comes to GNRs. Remarkably, the bipolaron dynamics can occur in acoustic and optical regimes concerning its saturation velocity. The phase transition between these two regimes takes place for a critical field strength in which the bipolaron moves roughly with the speed of sound in the material.</p>","","","","","","","","","","","","","2019-03-26","2019-03-26","2019-09-24","http://liu.diva-portal.org/smash/get/diva2:1299375/FULLTEXT01.pdf","","6","","1","","","","","2909","false","","",""
"1300651","Ning, Weihua [weini20] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Nanjing Tech Univ, Peoples R China);Zhao, Xin-Gang (Jilin Univ, Peoples R China);Klarbring, Johan [johkl85] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Bai, Sai [saiba14] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ji, Fuxiang [fuxji90] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Wang, Feng [fenwa69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Tao, Youtian (Nanjing Tech Univ, Peoples R China);Ren, Xiao-Ming (Nanjing Tech Univ, Peoples R China);Zhang, Lijun (Jilin Univ, Peoples R China);Huang, Wei (Nanjing Tech Univ, Peoples R China);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia);Gao, Feng [fenga88] [0000-0002-2582-1740] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Biomolekylär och Organisk Elektronik [2213]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Thermochromic Lead-Free Halide Double Perovskites","Artikel i tidskrift","Refereegranskat","eng","Advanced Functional Materials","1616-301X","1616-3028","published","29","10","","","","2019","","","","WILEY-V C H VERLAG GMBH","","","","","","","10.1002/adfm.201807375","000460474200013","","","urn:nbn:se:liu:diva-155529","","","Cs2AgBiBr6; lead-free double perovskites; smart windows; thermochromic films","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Knut and Alice Wallenberg Foundation; National Natural Science Foundation of China [61704078, 61722403]; Natural Science Foundation of Jiangsu Province of China [BK20160990]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [200900971]; European Commission Marie Skodowska-Curie actions [691210]; European Commission SOLAR-ERA.NET; Swedish Energy Agency (Energimyndigheten); Swedish Research Council (FORMAS); China Scholarship Council; Recruitment Program of Global Youth Experts in China; National Key Research and Development Program of China [2016YFB0201204]; Program for JLU Science and Technology Innovative Research Team; Swedish Research Council (VR) [2014-4750]; Ministry of Education and Science of the Russian Federation [074-02-2018-327]</p>","<p>Lead-free halide double perovskites with diverse electronic structures and optical responses, as well as superior material stability show great promise for a range of optoelectronic applications. However, their large bandgaps limit their applications in the visible light range such as solar cells. In this work, an efficient temperature-derived bandgap modulation, that is, an exotic fully reversible thermochromism in both single crystals and thin films of Cs2AgBiBr6 double perovskites is demonstrated. Along with the thermochromism, temperature-dependent changes in the bond lengths of Ag Symbol of the Klingon Empire Br (R-Ag Symbol of the Klingon Empire Br) and Bi Symbol of the Klingon Empire Br (R-Bi Symbol of the Klingon Empire Br) are observed. The first-principle molecular dynamics simulations reveal substantial anharmonic fluctuations of the R-Ag Symbol of the Klingon Empire Br and R-Bi Symbol of the Klingon Empire Br at high temperatures. The synergy of anharmonic fluctuations and associated electron-phonon coupling, and the peculiar spin-orbit coupling effect, is responsible for the thermochromism. In addition, the intrinsic bandgap of Cs2AgBiBr6 shows negligible changes after repeated heating/cooling cycles under ambient conditions, indicating excellent thermal and environmental stability. This work demonstrates a stable thermochromic lead-free double perovskite that has great potential in the applications of smart windows and temperature sensors. Moreover, the findings on the structure modulation-induced bandgap narrowing of Cs2AgBiBr6 provide new insights for the further development of optoelectronic devices based on the lead-free halide double perovskites.</p>","","","","","","","","","","","","","2019-03-29","2019-03-29","2019-09-24","","","13","","2","","","","","1807375","false","","",""
"1341140","Pilemalm, Robert [robpi36] [0000-0001-5670-7644] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Eklund, Per [perek02] [0000-0003-1785-0864] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Effects of high pressure on ScMN<sub>2</sub>-type (M = V, Nb, Ta) phases studied by density functional theory","Artikel i tidskrift","Refereegranskat","eng","Results in Physics","2211-3797","","published","13","","","","","2019","","","","Elsevier","","","","","","","10.1016/j.rinp.2019.102293","000476618700182","","","urn:nbn:se:liu:diva-159276","","","ScTaN2; Inverse MAX phase; High pressure; Density functional theory","Oorganisk kemi (10404)","","","<p>Funding Agencies|Swedish Research Council (VR) [2016-03365]; Knut and Alice Wallenberg Foundation through the Wallenberg Academy Fellows program; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]</p>","<p>ScMN2-type (M = V, Nb, Ta) phases are layered materials that have been experimentally reported for M = Ta and Nb, but their high-pressure properties have not been studied. Here, we have used first-principles calculations to study their thermodynamic stability, elastic and electronic properties at high-pressure. We have used density functional theory to calculate the formation enthalpy relative to the competing binary phases, electronic density of states and elastic constants (c(ij)), bulk (B), shear (G) and Youngs (E) modulus as the pressure is varied from 0 to 150 GPa. Our results show that when the pressure increases from 0 to 150 GPa, elastic constants, bulk, shear and elastic moduli increase in the range 53-216% for ScTaN2, 72-286% for ScNbN2, and 61-317% for ScVN2.</p>","","","","","","","","","","","","","2019-08-07","2019-08-07","2019-10-16","http://liu.diva-portal.org/smash/get/diva2:1341140/FULLTEXT01.pdf","","3","","1","urn:nbn:se:liu:diva-155101","","","","102293","true","true","",""
"1302145","Ferrari, Alberto (Ruhr Univ Bochum, Germany);Sangiovanni, Davide [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Ruhr Univ Bochum, Germany);Rogal, Jutta (Ruhr Univ Bochum, Germany);Drautz, Ralf (Ruhr Univ Bochum, Germany)","First-principles characterization of reversible martensitic transformations","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","99","9","","","","2019","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.99.094107","000461949200001","","","urn:nbn:se:liu:diva-156095","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Deutsche Forschungsgemeinschaft (DFG) [FOR 1766, 200999873]; Olle Engkvist Foundation</p>","<p>Reversible martensitic transformations (MTs) are the origin of many fascinating phenomena, including the famous shape memory effect. In this work, we present a fully ab initio procedure to characterize MTs in alloys and to assess their reversibility. Specifically, we employ ab initio molecular dynamics data to parametrize a Landau expansion for the free energy of the MT. This analytical expansion makes it possible to determine the stability of the high- and low-temperature phases, to obtain the Ehrenfest order of the MT, and to quantify its free energy barrier and latent heat. We apply our model to the high-temperature shape memory alloy Ti-Ta, for which we observe remarkably small values for the metastability region (the interval of temperatures in which the high-and low-temperature phases are metastable) and for the barrier: these small values are necessary conditions for the reversibility of MTs and distinguish shape memory alloys from other materials.</p>","","","","","","","","","","","","","2019-04-03","2019-04-03","2019-10-18","http://liu.diva-portal.org/smash/get/diva2:1302145/FULLTEXT01.pdf","","4","","2","","","","","094107","false","","",""
"1323835","Gautam, Rekha (San Francisco State Univ, CA 94132 USA; Vanderbilt Univ, TN 37240 USA);Xiang, Yinxiao (San Francisco State Univ, CA 94132 USA; Nankai Univ, Peoples R China; Nankai Univ, Peoples R China);Lamstein, Josh (San Francisco State Univ, CA 94132 USA);Liang, Yi (San Francisco State Univ, CA 94132 USA; Guangxi Univ, Peoples R China);Bezryadina, Anna (San Francisco State Univ, CA 94132 USA; Calif State Univ Northridge, CA 91330 USA);Liang, Guo (San Francisco State Univ, CA 94132 USA);Hansson, Tobias [tobha84] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Quebec, Canada);Wetzel, Benjamin (Univ Quebec, Canada; Univ Sussex, England);Preece, Daryl (Univ Calif Irvine, CA USA);White, Adam (San Francisco State Univ, CA 94132 USA);Silverman, Matthew (San Francisco State Univ, CA 94132 USA);Kazarian, Susan (San Francisco State Univ, CA 94132 USA);Xu, Jingjun (Nankai Univ, Peoples R China);Morandotti, Roberto (Univ Quebec, Canada; Univ Elect Sci and Tech China, Peoples R China; ITMO Univ, Russia);Chen, Zhigang (San Francisco State Univ, CA 94132 USA; Nankai Univ, Peoples R China; Nankai Univ, Peoples R China)","Optical force-induced nonlinearity and self-guiding of light in human red blood cell suspensions","Artikel i tidskrift","Refereegranskat","eng","Light: Science & Applications","2095-5545","2047-7538","published","8","","","","","2019","","","","CHINESE ACAD SCIENCES, CHANGCHUN INST OPTICS FINE MECHANICS AND PHYSICS","","","","","","","10.1038/s41377-019-0142-1","000463971300003","30886708","","urn:nbn:se:liu:diva-157260","","","","Annan fysik (10399)","","","<p>Funding Agencies|NIH (USA); NSF (USA); ARO (USA); National Key R&D Program of China [2017YFA0303800]; National Natural Science Foundation of China [91750204, 11504184, 11604058]; NSERC; Canada Research Chair Program (Canada); Government of the Russian Federation through the ITMO Fellowship and Professorship Program [074-U 01]; 1000 Talents Sichuan Program in China</p>","<p>Osmotic conditions play an important role in the cell properties of human red blood cells (RBCs), which are crucial for the pathological analysis of some blood diseases such as malaria. Over the past decades, numerous efforts have mainly focused on the study of the RBC biomechanical properties that arise from the unique deformability of erythrocytes. Here, we demonstrate nonlinear optical effects from human RBCs suspended in different osmotic solutions. Specifically, we observe self-trapping and scattering-resistant nonlinear propagation of a laser beam through RBC suspensions under all three osmotic conditions, where the strength of the optical nonlinearity increases with osmotic pressure on the cells. This tunable nonlinearity is attributed to optical forces, particularly the forward-scattering and gradient forces. Interestingly, in aged blood samples (with lysed cells), a notably different nonlinear behavior is observed due to the presence of free hemoglobin. We use a theoretical model with an optical force-mediated nonlocal nonlinearity to explain the experimental observations. Our work on light self-guiding through scattering bio-soft-matter may introduce new photonic tools for noninvasive biomedical imaging and medical diagnosis.</p>","","","","","","","","","","","","","2019-06-12","2019-06-12","2019-10-30","http://liu.diva-portal.org/smash/get/diva2:1323835/FULLTEXT01.pdf","","15","","1","","","","","31","false","","",""
"1328782","Krasilnikov, O. M. (NUST MISIS, Russia);Lugovskoy, A. V (NUST MISIS, Russia; Radboud Univ Nijmegen, Netherlands);Dikan, V (NUST MISIS, Russia; CSIC, Spain);Belov, M. P. (NUST MISIS, Russia);Vekilov, Yu Kh (NUST MISIS, Russia);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (NUST MISIS, Russia)","Nonlinear elasticity of epsilon -Fe: The pressure effect","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","99","18","","","","2019","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.99.184101","000467381200001","","","urn:nbn:se:liu:diva-157529","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Russian Science Foundation [18-12-00492]; Swedish Research Council [2015-04391]</p>","<p>Description of elasticity of iron at the ultrahigh pressures is a challenging task for physics, with a potential strong impact on other branches of science. In the present work, we calculate the elastic properties of hcp iron in the pressure range of 50-340 GPa beyond the linear elasticity approximation, conventionally assumed in theoretical studies. We define the higher order elastic constants and present expressions for the long-wave acoustic modes Gruneisen parameters of a compressed hcp crystal. We obtain the second and third order elastic constants of the hcp Fe in the considered pressure interval, as well as its Gruneisen parameters for the high-symmetry directions. The latter are directly compared with the Gruneisen parameters derived from the volume dependences of the vibrational frequencies calculated in the quasiharmonic approximation. The obtained results are used for the stability analysis of the hcp phase of iron at high pressures.</p>","","","","","","","","","","","","","2019-06-23","2019-06-23","2019-11-04","http://liu.diva-portal.org/smash/get/diva2:1328782/FULLTEXT01.pdf","","6","","2","","","","","184101","false","","",""
"1330181","Ekholm, Marcus [marek10] [0000-0002-7563-1494] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Bayreuth, Germany);Schoenleber, A. (Univ Bayreuth, Germany);van Smaalen, S. (Univ Bayreuth, Germany)","The role of magnetic order in VOCl","Artikel i tidskrift","Refereegranskat","eng","Journal of Physics: Condensed Matter","0953-8984","1361-648X","published","31","32","","","","2019","","","","IOP PUBLISHING LTD","","","","","","","10.1088/1361-648X/ab1eff","000469014700001","31048571","","urn:nbn:se:liu:diva-158038","","","vanadium oxychloride; soditun ion battery; chloride ion battery; magnetic insulators; strong correlations","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Swedish e-Science Research Centre (SeRC); Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) [386411512]</p>","<p>VOCl and other transition metal oxychlorides are candidate materials for next-generation rechargeable batteries. We have investigated the influence of the underlying magnetic order on the crystallographic and electronic structure by means of density functional theory. Our study shows that antiferromagnetic ordering explains the observed low-temperature monoclinic distortion of the lattice, which leads to a decreased distance between antiferromagnetically coupled V-V nearest neighbors. We also show that the existence of a local magnetic moment removes the previously suggested degeneracy of the occupied levels, in agreement with experiments. To describe the electronic structure, it turns out crucial to take the correct magnetic ordering into account, especially at elevated temperature.</p>","","","","","","","","","","","","","2019-06-25","2019-06-25","2019-11-04","http://liu.diva-portal.org/smash/get/diva2:1330181/FULLTEXT01.pdf","","3","","1","","","","","325502","false","","",""
"1361446","Pilemalm, Robert [robpi36] [0000-0001-5670-7644] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Simak, Sergei [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Eklund, Per [perek02] [0000-0003-1785-0864] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902])","The Effect of Point Defects on the Electronic Density of States of ScMN<sub>2</sub>-Type (M = V, Nb, Ta) Phases","Artikel i tidskrift","Refereegranskat","eng","Condensed Matter","2410-3896","","published","4","3","","","","2019","","","","MDPI","","","","","","","10.3390/condmat4030070","000487966200001","","","urn:nbn:se:liu:diva-160948","","","ScTaN2; YNbN2; inverse MAX phase; point defect; density of states","Fysik (103)","","","<p>Funding agencies: Swedish Research Council (VR)Swedish Research Council [2016-03365]; Knut and Alice Wallenberg Foundation through the Wallenberg Academy Fellows program; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping U</p>","<p>ScMN<sub>2</sub>-type (M = V, Nb, Ta) phases are layered materials that have been experimentally reported for M = Ta and Nb. They are narrow-bandgap semiconductors with potentially interesting thermoelectric properties. Point defects such as dopants and vacancies largely affect these properties, motivating the need to investigate these effects. In particular, asymmetric peak features in the density of states (DOS) close to the highest occupied state is expected to increase the Seebeck coefficient. Here, we used first principles calculations to study the effects of one vacancy or one C, O, or F dopant on the DOS of the ScMN<sub>2</sub> phases. We used density functional theory to calculate formation energy and the density of states when a point defect is introduced in the structures. In the DOS, asymmetric peak features close to the highest occupied state were found as a result of having a vacancy in all three phases. Furthermore, one C dopant in ScTaN<sub>2</sub>, ScNbN<sub>2</sub>, and ScVN<sub>2</sub> implies a shift of the highest occupied state into the valence band, while one O or F dopant causes a shift of the highest occupied state into the conduction band.</p>","","","","","","","","","","","","","2019-10-16","2019-10-16","2019-11-04","http://liu.diva-portal.org/smash/get/diva2:1361446/FULLTEXT01.pdf","","3","","1","urn:nbn:se:liu:diva-155101","","","","70","true","true","",""
"1334902","Belonoshko, Anatoly B. (Royal Inst Technol KTH, Sweden);Fu, Jie (Ningbo Univ, Peoples R China);Bryk, Taras (Natl Acad Sci Ukraine, Ukraine);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Mattesini, Maurizio (Univ Complutense Madrid, Spain; UCM, Spain)","Low viscosity of the Earths inner core","Artikel i tidskrift","Refereegranskat","eng","Nature Communications","2041-1723","2041-1723","published","10","","","","","2019","","","","NATURE PUBLISHING GROUP","","","","","","","10.1038/s41467-019-10346-2","000470248100015","31171778","","urn:nbn:se:liu:diva-158548","","","","Fysikalisk kemi (10402)","","","<p>Funding Agencies|Swedish Research Council (VR) [2013-5767, 2014-4750, 2017-03744]; National Natural Science Foundation of China [11804175]; Olle Engkvist Byggmastare Foundation; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-MatLiU) [2009 00971]; Spanish Ministry of Economy and Competitiveness [CGL2013-41860-P, CGL2017-86070-R]</p>","<p>The Earths solid inner core is a highly attenuating medium. It consists mainly of iron. The high attenuation of sound wave propagation in the inner core is at odds with the widely accepted paradigm of hexagonal close-packed phase stability under inner core conditions, because sound waves propagate through the hexagonal iron without energy dissipation. Here we show by first-principles molecular dynamics that the body-centered cubic phase of iron, recently demonstrated to be thermodynamically stable under the inner core conditions, is considerably less elastic than the hexagonal phase. Being a crystalline phase, the body-centered cubic phase of iron possesses the viscosity close to that of a liquid iron. The high attenuation of sound in the inner core is due to the unique diffusion characteristic of the body-centered cubic phase. The low viscosity of iron in the inner core enables the convection and resolves a number of controversies.</p>","","","","","","","","","","","","","2019-07-03","2019-07-03","2019-11-06","http://liu.diva-portal.org/smash/get/diva2:1334902/FULLTEXT01.pdf","","5","","2","","","","","2483","false","","",""
"1338146","Pakhomova, Anna (DESY, Germany);Aprilis, Georgios (Univ Bayreuth, Germany);Bykov, Maxim (Univ Bayreuth, Germany);Gorelova, Liudmila (St Petersburg State Univ, Russia);Krivovichev, Sergey S. (St Petersburg State Univ, Russia; Russian Acad Sci, Russia);Belov, Maxim P. (NUST MISIS, Russia);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Dubrovinsky, Leonid (Univ Bayreuth, Germany)","Penta- and hexa-coordinated beryllium and phosphorus in high-pressure modifications of CaBe2P2O8","Artikel i tidskrift","Refereegranskat","eng","Nature Communications","2041-1723","2041-1723","published","10","","","","","2019","","","","NATURE PUBLISHING GROUP","","","","","","","10.1038/s41467-019-10589-z","000472840400015","31243286","","urn:nbn:se:liu:diva-158965","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Ministry of Science and High Education of the Russian Federation [K2-2019-001]; Russian Foundation for Basic Research [19-02-00871]; Swedish Research Council (VR) [2015-04391]; Swedish Government Strategic Research Areas in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; SeRC</p>","<p>Beryllium oxides have been extensively studied due to their unique chemical properties and important technological applications. Typically, in inorganic compounds beryllium is tetrahedrally coordinated by oxygen atoms. Herein based on results of in situ single crystal X-ray diffraction studies and ab initio calculations we report on the high-pressure behavior of CaBe2P2O8, to the best of our knowledge the first compound showing a step-wise transition of Be coordination from tetrahedral (4) to octahedral (6) through trigonal bipyramidal (5). It is remarkable that the same transformation route is observed for phosphorus. Our theoretical analysis suggests that the sequence of structural transitions of CaBe2P2O8 is associated with the electronic transformation from predominantly molecular orbitals at low pressure to the state with overlapping electronic clouds of anions orbitals.</p>","","","","","","","","","","","","","2019-07-19","2019-07-19","2019-11-12","http://liu.diva-portal.org/smash/get/diva2:1338146/FULLTEXT01.pdf","","8","","2","","","","","2800","false","","",""
"1343996","Landälv, Ludvig [ludla97] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Sandvik Coromant AB, Stockholm, Sweden);Carlström, C-F (Sandvik Coromant AB, Stockholm, Sweden);Lu, Jun [junlu07] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Primetzhofer, D. (Applied Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden);Jöesaar, M. J. (SECO Tools AB, Fagersta, Sweden);Ahlgren, M. (Sandvik Coromant AB, Stockholm, Sweden);Göthelid, E. (Sandvik Coromant AB, Stockholm, Sweden);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Hultman, Lars [larhu75] [0000-0002-2837-3656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Eklund, Per [perek02] [0000-0003-1785-0864] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Phase composition and transformations in magnetron-sputtered (Al,V)2O3 coatings","Artikel i tidskrift","Refereegranskat","eng","Thin Solid Films","0040-6090","1879-2731","published","688","","","","","2019","","","","Elsevier","","","","","https://arxiv.org/abs/1905.06714","","10.1016/j.tsf.2019.06.019","000485256500035","","","urn:nbn:se:liu:diva-159749","","","Aluminum vanadium oxide Pulsed DC magnetron sputtering Annealing V2O5 AlVO4 AlVO3","Fysik (103)","","","","<p>Coatings of (Al<sub>1-x</sub>V<sub>x</sub>)<sub>2</sub>O<sub>3</sub>, with x ranging from 0 to 1, were deposited by pulsed DC reactive sputter deposition on Si(100) at a temperature of 550 °C. XRD showed three different crystal structures depending on V-metal fraction in the coating: α-V<sub>2</sub>O<sub>3</sub> rhombohedral structure for 100 at.% V, a defect spinel structure for the intermediate region, 63–42 at.% V. At lower V-content, 18 and 7 at.%, a gamma-alumina-like solid solution was observed, shifted to larger d-spacing compared to pure γ-Al<sub>2</sub>O<sub>3</sub>. The microstructure changes from large columnar faceted grains for α-V<sub>2</sub>O<sub>3</sub> to smaller equiaxed grains when lowering the vanadium content towards pure γ-Al<sub>2</sub>O<sub>3</sub>. Annealing in air resulted in formation of V<sub>2</sub>O<sub>5</sub> crystals on the surface of the coating after annealing to 500 °C for 42 at.% V and 700 °C for 18 at.% V metal fraction respectively. The highest thermal stability was shown for pure γ-Al<sub>2</sub>O<sub>3</sub>-coating, which transformed to α-Al<sub>2</sub>O<sub>3</sub> after annealing to 1100 °C. Highest hardness was observed for the Al-rich oxides, ~24 GPa. The latter decreased with increasing V-content, larger than 7 at.% V metal fraction. The measured hardness after annealing in air decreased in conjunction with the onset of further oxidation of the coatings.</p>","","","","","","","","","","","","","2019-08-20","2019-08-20","2019-11-14","http://liu.diva-portal.org/smash/get/diva2:1343996/FULLTEXT01.pdf","","10","","1","urn:nbn:se:liu:diva-156603","","","","137369","true","","",""
"1341166","Xu, Bin (Soochow Univ, Peoples R China; Univ Arkansas, AR 72701 USA; Univ Arkansas, AR 72701 USA);Hellman, Olle [olohe96] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Bellaiche, L. (Univ Arkansas, AR 72701 USA)","Order-disorder transition in the prototypical antiferroelectric PbZrO3","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","100","2","","","","2019","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.100.020102","000476685600001","","","urn:nbn:se:liu:diva-159247","","","","Teoretisk kemi (10407)","","","<p>Funding Agencies|ONR [N00014-17-1-2818]; DARPA under the MATRIX program [HR0011-15-2-0038]; Priority Academic Program Development (PAPD) of Jiangsu Higher Education Institutions; Arkansas High Performance Computer Center at the University of Arkansas; Cloud Pilot project</p>","<p>The prototypical antiferroelectric PbZrO3 has several unsettled questions, such as the nature of the antiferroelectric transition, a possible intermediate phase, and the microscopic origin of the Pbam ground state. Using first-principles calculations, we show that no phonon becomes truly soft at the cubic-to-Pbam transition temperature, and the order-disorder character of this transition is clearly demonstrated based on molecular dynamics simulations and potential energy surfaces. The out-of-phase octahedral tilting is an important degree of freedom, which can collaborate with other phonon distortions and form a complex energy landscape with multiple minima Candidates of the possible intermediate phase are suggested based on the calculated kinetic barriers between energy minima, and the development of a first-principles-based effective Hamiltonian. The use of this latter scheme further reveals that specific bilinear interactions between local dipoles and octahedral tiltings play a major role in the formation of the Pbam ground state, which contrasts with most of the previous explanations.</p>","","","","","","","","","","","","","2019-08-07","2019-08-07","2019-11-15","http://liu.diva-portal.org/smash/get/diva2:1341166/FULLTEXT01.pdf","","3","","2","","","","","020102","false","","",""
"1368853","Ekeroth, Sebastian [sebek07] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Plasma och beläggningsfysik [2225]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ikeda, Shuga (Department of Intelligent Mechanical Systems, Tokyo Metropolitan University, Tokyo, Japan);Boyd, Robert [robbo87] [0000-0002-6602-7981] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Plasma och beläggningsfysik [2225]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Münger, Peter [petmu26] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Shimizu, Tetsuhide (Department of Intelligent Mechanical Systems, Tokyo Metropolitan University, Tokyo, Japan);Helmersson, Ulf [ulfhe30] [0000-0002-1744-7322] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Plasma och beläggningsfysik [2225]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Impact of nanoparticle magnetization on the 3D formation of dual-phase Ni/NiO nanoparticle-based nanotrusses","Artikel i tidskrift","Refereegranskat","eng","Journal of nanoparticle research","1388-0764","1572-896X","published","21","11","","","","2019","","","","Springer-Verlag New York","","","","","","","10.1007/s11051-019-4661-8","000494039300001","","","urn:nbn:se:liu:diva-161747","","","Ni;NiO;Nanotruss;Nanoparticle;Magnetic assembly","Materialkemi (10403)","","","<p>Funding agencies</p>","<p>Magnetic nanoparticles with average size 30 nm were utilized to build three-dimensional framework structures—nanotrusses. In dual-phase Ni/NiO nanoparticles, there is a strong correlation between the amount of magnetic Ni and the final size and shape of the nanotruss. As it decreases, the length of the individual nanowires within the trusses also decreases, caused by a higher degree of branching of the wires. The position and orientation of the non-magnetic material within the truss structure was also investigated for the different phase compositions. For lower concentrations of NiO phase, the electrically conducting Ni-wire framework is maintained through the preferential bonding between the Ni crystals. For larger concentrations of NiO phase, the Ni-wire framework is interrupted by the NiO. The ability to use nanoparticles that are only partly oxidized in the growth of nanotruss structures is of great importance. It opens the possibility for using not only magnetic metals such as pure Ni, Fe, and Co, but also to use dual-phase nanoparticles that can strongly increase the efficiency of e.g. catalytic electrodes and fuel cells.</p>","","","","","","","","","","","","","2019-11-08","2019-11-08","2019-11-19","http://liu.diva-portal.org/smash/get/diva2:1368853/FULLTEXT01.pdf","","6","","1","urn:nbn:se:liu:diva-161300","","","","21:228","true","true","",""
"1353576","Leonov, Ivan (Russian Acad Sci, Russia; Natl Univ Sci and Technol MISIS, Russia);Rozenberg, Gregory Kh (Tel Aviv Univ, Israel);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia)","Charge disproportionation and site-selective local magnetic moments in the post-perovskite-type Fe2O3 under ultra-high pressures","Artikel i tidskrift","Refereegranskat","eng","NPJ COMPUTATIONAL MATERIALS","2057-3960","","published","5","","","","","2019","","","","SPRINGERNATURE","","","","","","","10.1038/s41524-019-0225-9","000483610700001","","","urn:nbn:se:liu:diva-160392","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Russian Science Foundation [18-12-00492]; Swedish Research Council [2015-04391]; Swedish Government Strategic Research Areas in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; Swedish e-Science Research Centre (SeRC); Israeli Science Foundation [1189/14, 1552/18]</p>","<p>The archetypal 3d Mott insulator hematite, Fe2O3, is one of the basic oxide components playing an important role in mineralogy of Earths lower mantle. Its high pressure-temperature behavior, such as the electronic properties, equation of state, and phase stability is of fundamental importance for understanding the properties and evolution of the Earths interior. Here, we study the electronic structure, magnetic state, and lattice stability of Fe2O3 at ultra-high pressures using the density functional plus dynamical mean-field theory (DFT + DMFT) approach. In the vicinity of a Mott transition, Fe2O3 is found to exhibit a series of complex electronic, magnetic, and structural transformations. In particular, it makes a phase transition to a metal with a post-perovskite crystal structure and site-selective local moments upon compression above 75 GPa. We show that the site-selective phase transition is accompanied by a charge disproportionation of Fe ions, with Fe-3 +/-delta and delta similar to 0.05-0.09, implying a complex interplay between electronic correlations and the lattice. Our results suggest that site-selective local moments in Fe2O3 persist up to ultra-high pressures of similar to 200-250 GPa, i.e., sufficiently above the core-mantle boundary. The latter can have important consequences for understanding of the velocity and density anomalies in the Earths lower mantle.</p>","","","","","","","","","","","","","2019-09-23","2019-09-23","2019-12-03","http://liu.diva-portal.org/smash/get/diva2:1353576/FULLTEXT01.pdf","","3","","0","","","","","90","false","","",""
"1357454","Li, Huanyu [huali50] [0000-0003-1881-3969] (Linköpings universitet [276], Institutionen för datavetenskap [281], Databas och informationsteknik [11105]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Armiento, Rickard [ricar47] [0000-0002-5571-0814] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Lambrix, Patrick [patla00] [0000-0002-9084-0470] (Linköpings universitet [276], Institutionen för datavetenskap [281], Databas och informationsteknik [11105]) (Linköpings universitet [276], Tekniska högskolan [1751]) (IDA/ADIT)","A Method for Extending Ontologies with Application to the Materials Science Domain","Artikel i tidskrift","Refereegranskat","eng","Data Science Journal","1683-1470","1683-1470","published","18","1","","1","21","2019","","","","Ubiquity Press","","","","","","","10.5334/dsj-2019-050","","","","urn:nbn:se:liu:diva-160711","","","Ontology;Materials Science;Nanotechnology;Nanoparticle;Topic Model;Formal Topical Concept Analysis","Datavetenskap (datalogi) (10201);Materialteknik (205)","","","","<p>In the materials science domain the data-driven science paradigm has become the focus since the beginning of the 2000s. A large number of research groups and communities are building and developing data-driven workflows. However, much of the data and knowledge is stored in different heterogeneous data sources maintained by different groups. This leads to a reduced availability of the data and poor interoperability between systems in this domain. Ontology-based techniques are an important way to reduce these problems and a number of efforts have started. In this paper we investigate efforts in the materials science, and in particular in the nanotechnology domain, and show how such ontologies developed by domain experts, can be improved. We use a phrase-based topic model approach and formal topical concept analysis on unstructured text in this domain to suggest additional concepts and axioms for the ontology that should be validated by a domain expert. We describe the techniques and show the usefulness of the approach through an experiment where we extend two nanotechnology ontologies using approximately 600 titles and abstracts.</p>","","","","","","","","","","","","","2019-10-03","2019-10-03","2019-12-03","http://liu.diva-portal.org/smash/get/diva2:1357454/FULLTEXT01.pdf","Swedish e‐Science Research Center;Vetenskapsrådet [2018-04147];CUGS (National Graduate School in Computer Science)","3","","1","","","","","50","true","","",""
"1362722","Heine, Matthew (Boston Coll, MA 02467 USA);Hellman, Olle [olohe96] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Broido, David (Boston Coll, MA 02467 USA)","Effect of thermal lattice and magnetic disorder on phonons in bcc Fe: A first-principles study","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","100","10","","","","2019","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.100.104304","000485311800002","","","urn:nbn:se:liu:diva-160589","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|National Science Foundation EFRI 2-DARE program [1433467]; Boston College dissertation fellowship award; National Science FoundationNational Science Foundation (NSF) [ACI-1548562]; NSFNational Science Foundation (NSF) [ACI-1445606]</p>","<p>We present a first-principles theoretical approach to calculate temperature dependent phonon dispersions in bcc Fe, which captures finite temperature spin-lattice coupling by treating thermal disorder in both the spin and lattice systems simultaneously. With increasing temperature, thermal atomic displacements are found to induce increasingly large fluctuations in local magnetic moment magnitudes. The calculated phonon dispersions of bcc Fe show excellent agreement with measured data over a wide range of temperatures both above and below the magnetic and structural transition temperatures, suggesting the applicability of the developed approach to other magnetic materials.</p>","","","","","","","","","","","","","2019-10-21","2019-10-21","2019-12-06","http://liu.diva-portal.org/smash/get/diva2:1362722/FULLTEXT01.pdf","","3","","2","","","","","104304","false","","",""
"1349020","Pedersen, Henrik [henpe50] [0000-0002-7171-5383] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Kemi [9600]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Högberg, Hans [hanho47] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ektarawong, Annop [annek02] [0000-0002-6059-6833] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Chulalongkorn Univ, Thailand; Commiss Higher Educ, Thailand)","Thermodynamic stability of hexagonal and rhombohedral boron nitride under chemical vapor deposition conditions from van der Waals corrected first principles calculations","Artikel i tidskrift","Refereegranskat","eng","Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films","0734-2101","1520-8559","published","37","4","","","","2019","","","","A V S AMER INST PHYSICS","","","","","","","10.1116/1.5107455","000480781300020","","","urn:nbn:se:liu:diva-160062","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|Swedish Foundation for Strategic Research (SSF) [IS14-0027]; Swedish Government Strategic Research Area in Materials Science on Advanced Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; SSF through the Future Research Leaders 6 grant; Swedish Research Council (VR) [2014-6336]; Marie Sklodowska Curie Actions [INCA 600398]; Kungl. Ingenjorsvetenskapsakademiens Hans Werthen-Fond</p>","<p>Thin films of boron nitride (BN), particularly the sp(2)-hybridized polytypes hexagonal BN (h-BN) and rhombohedral BN (r-BN), are interesting for several electronic applications, given the bandgaps in the UV. They are typically deposited close to thermal equilibrium by chemical vapor deposition (CVD) at temperatures and pressures in the regions 1400-1800K and 1000-10000Pa, respectively. In this letter, the authors use the van der Waals corrected density functional theory and thermodynamic stability calculations to determine the stability of r-BN and compare it to that of h-BN as well as to cubic BN and wurtzitic BN. The authors find that r-BN is the stable sp(2)-hybridized phase at CVD conditions, while h-BN is metastable. Thus, their calculations suggest that thin films of h-BN must be deposited far from thermal equilibrium.</p>","","","","","","","","","","","","","2019-09-06","2019-09-06","2019-12-30","http://liu.diva-portal.org/smash/get/diva2:1349020/FULLTEXT01.pdf","","4","","1","","","","","040603","false","","",""
"1370230","Sangiovanni, Davide [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Ruhr Univ Bochum, Germany)","Mass transport properties of quasiharmonic vs. anharmonic transition-metal nitrides","Artikel i tidskrift","Refereegranskat","eng","Thin Solid Films","0040-6090","1879-2731","published","688","","","","","2019","","","","ELSEVIER SCIENCE SA","","","","","","","10.1016/j.tsf.2019.05.016","000485256500027","","","urn:nbn:se:liu:diva-160975","","","Nitrides; Diffusion; Ab initio; Molecular dynamics; Vacancies; Lattice dynamics; Anharmonicity; Transition-state theory","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Olle Engkvist Foundation; VINN Excellence Center Functional Nanoscale Materials (FunMat-2) [2016-05156]</p>","<p>I present a development of the color-diffusion algorithm, used in non-equilibrium (accelerated) ab initio molecular dynamics simulations of point-defect migration in crystals [Sangiovanni et al., Phys. Rev. B 93, 094305 (2016)], to determine the temperature dependence of anion vacancy jump frequencies in rocksalt-structure (B1) TiN and VN characterized by quasiharmonic (TiN) vs. strongly anharmonic (VN) lattice dynamics. Over a temperature range [ 0.6""Tm amp;lt; T amp;lt; 0.9 T-m] relatively close to the materials melting points Tm, the simulations reveal that anion vacancy migration in TiN and VN exhibits an Arrhenius-like behavior, described by activation energies EJN = 4.2 0.3 eV and EZN = 3.1 0.3 eV, and attempt frequencies vTN = 8.1015 0.7 s-1 and vvN = 2.1017 c).8s-1. A comparison of activation energies E extracted by Arrhenius linear regression at elevated temperatures with ab initio E,,ca values calculated at 0 Kelvin reveals that, while the nitrogen migration energy amp;ills varies modestly with temperature {AEPN = [E-a(T-m)- Ea(0 K)1/Ea(0 K) 0.1}, the changes in EavN vs. T are considerable (AEavN 1). The temperature-induced variations in vacancy migration energies and diffusivities are discussed in relation to the TiN and VN vibrational properties determined via ab initio molecular dynamics at different temperatures. It is argued that static 0-K calculations, which account for thermal expansion effects within the framework of quasiharmonic transition-state theory, accurately reproduce the finite-temperature mass transport properties of TiN. Conversely, the use of molecular dynamics simulations, which explicit treat lattice vibrations at any temperature of interest, is necessary to achieve reliable atomic diffusivities in B1 VN, a crystal phase dynamically stabilized by anharmonic vibrations [Mei et al., Phys. Rev. B 91, 054101 (2015)].</p>","","","","","","","","","","","","","2019-11-14","2019-11-14","2020-01-13","","","1","","1","","","","","137297","false","","",""
"1370248","Edström, Daniel [daned22] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Orebro Univ, Sweden);Sangiovanni, Davide [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Ruhr Univ Bochum, Germany);Hultman, Lars [larhu75] [0000-0002-2837-3656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Petrov, Ivan [ivape26] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Illinois, IL 61801 USA);Greene, Joseph E [josgr17] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Illinois, IL 61801 USA; Natl Taiwan Univ Sci and Technol, Taiwan);Chirita, Valeriu [valch35] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902])","TiN film growth on misoriented TiN grains with simultaneous low-energy bombardment: Restructuring leading to epitaxy","Artikel i tidskrift","Refereegranskat","eng","Thin Solid Films","0040-6090","1879-2731","published","688","","","","","2019","","","","ELSEVIER SCIENCE SA","","","","","","","10.1016/j.tsf.2019.06.030","000485256500051","","","urn:nbn:se:liu:diva-160969","","","Titanium nitride; Molecular dynamics; Film growth simulations; Epitaxy","Oorganisk kemi (10404)","","","<p>Funding Agencies|Swedish Research Council (VR) Linkoping Linnaeus Initiative LiLi-NFM [2008-6572]; Swedish Government Strategic Research Area Grant in Materials Science on Advanced Functional Materials; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation; Olle Engkvist Foundation; VinnovaVinnova [2016-05156]; Swedish Research Council (VR)Swedish Research Council [2009-00971, 2013-4018, 2014-5790]</p>","<p>We perform large-scale molecular dynamics simulations of TiN deposition at 1200 K on TiN substrates consisting of under-stoichiometric (N/Ti = 0.86) misoriented grains. The energy of incoming Ti atoms is 2 eV and that of incoming N atoms is 10 eV. The simulations show that misoriented grains are reoriented during the early stages of growth, after which the film grows 001 epitaxially and is nearly stoichiometric. The grain reorientation coincides with an increase in film N/Ti ratio. As the grains reorient, additional nitrogen can no longer be accommodated, and the film composition becomes stoichiometric as the overlayer grows epitaxially.</p>","","","","","","","","","","","","","2019-11-14","2019-11-14","2020-01-13","","","6","","1","","","","","137380","false","","",""
"1365689","Marcus, Carina [carma08] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Saab AB, Broderna Ugglas Vag, SE-58188 Linkoping, Sweden; Swedish Def Univ, Sweden)","Aspects of the design, evaluation and accuracy of airborne sensor clusters using time-difference of arrival","Artikel i tidskrift","Refereegranskat","eng","Aerospace Science and Technology","1270-9638","1626-3219","published","92","","","892","900","2019","","","","ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER","","","","","","","10.1016/j.ast.2019.07.025","000485852600074","","","urn:nbn:se:liu:diva-161194","","","Design Space Exploration; TDOA; Accuracy; Passive; Estimation; Source position; Sensor cluster","Rymd- och flygteknik (20302)","","","","<p>One way of improving situational awareness without increasing the risk of detection is to use passive sensor systems. If this capability is provided by several aircraft in a cluster, which can incorporate small basic sensor platforms, advantages can be gained such as longer baselines and an increased number of sensors in the cluster. In this paper, a methodology is presented that links results from signal processing to a Design Space Exploration, DSE, regarding sensor clusters when designing clusters that can operate both independently and in cooperation with other systems. When using Time-Difference of Arrival, the accuracy of the estimated location of a signal source depends on errors in timing and positioning of the sensors, errors in estimating signal arrival times and number of sensors and their spatial distribution. The Cramer-Rao Lower Bound is used to investigate the accuracy of signal source estimates for five different clusters and two levels of timing and positioning accuracy. The results show that the direction of arrival estimates are more accurate than those for the range. Although more sensors generally increased the accuracy, their spatial distribution and baseline related to the distance to the signal source also influence the quality of the results. The DSE process is supported by the collected presentation of the data regarding the measurement accuracy of the different sensor configurations, incorporating both cluster configuration as well as the positioning and timing. Having readily accessible data, the decision makers can focus on choosing the sensor system that meets the operational needs. (C) 2019 Elsevier Masson SAS. All rights reserved.</p>","","","","","","","","","","","","","2019-10-25","2019-10-25","2020-02-17","","","1","","1","urn:nbn:se:liu:diva-163595","","","","","false","","",""
"1367040","Marcus, Carina [carma08] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Saab AB, Aeronaut, Broderna Ugglas Gata, SE-58188 Linkoping, Sweden; Swedish Def Univ, Sweden);Raf, Martin (Saab AB, Aeronaut, Broderna Ugglas Gata, SE-58188 Linkoping, Sweden)","Detection Chain Model Designed for Aircraft Concept Development","Artikel i tidskrift","Refereegranskat","eng","Journal of Aircraft","0021-8669","1533-3868","published","56","5","","1942","1950","2019","","","","AMER INST AERONAUTICS ASTRONAUTICS","","","","","","","10.2514/1.C034930","000489572700017","","","urn:nbn:se:liu:diva-161415","","","","Rymd- och flygteknik (20302)","","","","<p>Simultaneous design of an aircraft and its sensor systems offers advantages over integrating standard sensors because the need for sensor function can be balanced against the integration issues. A model of the detection chain is here defined as mathematical representations of the sensors, the wave propagation, and the signatures of the target. When used in aircraft concept development in a design space exploration context, the model of the detection chain needs to be simple yet detailed enough to sufficiently describe both the sensor performance and the impact it has on the infrastructure of the aircraft. In this paper a detection chain model for radar is introduced. It includes the detection range, search volume, and signature together with implications in terms of the aircraft infrastructure the parameters of mass, the volume, and power and cooling requirements as a function of antenna size. The best choice of radar cannot be determined by the sensor function alone; it has to be evaluated together with the aircraft in tactical simulations in order to obtain the complete picture. The benefits of a larger antenna can, to some degree, be counteracted by the changes to the aircraft that affect its flight performance.</p>","","","","","","","","","","","","","2019-10-31","2019-10-31","2020-02-17","","","2","","1","urn:nbn:se:liu:diva-163595","","","","","false","","",""
"1395040","Johansson, Magnus [magjo23] [0000-0001-6708-1560] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]);Lobanov, Valery E. (Russian Quantum Center);Skryabin, Dmitry V. (University of Bath)","Stability analysis of numerically exact time-periodic breathers in the Lugiato-Lefever equation: Discrete vs continuum","Artikel i tidskrift","Refereegranskat","eng","Physical Review Research","2643-1564","","published","1","3","","1","9","2019","","","","American Physical Society","","","","","https://doi.org/10.1103/PhysRevResearch.1.033196","","10.1103/PhysRevResearch.1.033196","","","","urn:nbn:se:liu:diva-163824","","","Optical solitons;breathers;waveguide arrays","Fysik (103)","","","","<p>We describe a framework for numerical calculation of time-periodically oscillating (breather) solutions to the discretized Lugiato-Lefever equation (LLE), as well as their linear stability as obtained from numerical Floquet analysis. Compared to earlier approaches, our work allows for the following conclusions: (i) The complete families of solutions are obtained also in regimes of instability; (ii) analysis of Floquet spectra and the corresponding eigenvectors show clearly the nature of the various Hopf and period-doubling bifurcations; (iii) properties of breather solutions to the continuous LLE are connected to corresponding oscillating solutions of the discrete LLE, which is of interest in its own right modeling coupled nonlinear cavities. In particular, we show that the oscillating discrete cavity solitons found in earlier work can be viewed as lattice versions of the continuous LLE breathers, as there is a smooth continuation in parameter space connecting them. Moreover, we confirm the existence of stable breathers at large detunings that was recently observed experimentally and describe their appearance from bifurcations.</p>","","","","","","","","","","","","","2020-02-20","2020-02-20","2020-03-17","http://liu.diva-portal.org/smash/get/diva2:1395040/FULLTEXT01.pdf","EU, Horisont 2020 [691011]","3","","0","","","","","033196","false","true","",""
"1337600","Jönsson, Johan [johjo06] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ekholm, Marcus [marek10] [0000-0002-7563-1494] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Bykov, Maxim (Univ Bayreuth, Germany);Dubrovinsky, Leonid (Univ Bayreuth, Germany);van Smaalen, Sander (Univ Bayreuth, Germany);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia)","Inverse pressure-induced Mott transition in TiPO4","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","99","24","","","","2019","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.99.245132","000471984200002","","","urn:nbn:se:liu:diva-158863","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Knut and Alice Wallenberg Foundation [KAW-2013.0020]; Swedish e-Science Research Centre (SeRC); Swedish Research Council (VR) [2015-04391]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; Russian Science Foundation [18-12-00492]</p>","<p>TiPO4 shows interesting structural and magnetic properties as temperature and pressure are varied, such as a spin-Peierls phase transition and the development of incommensurate modulations of the lattice. Recently, high-pressure experiments for TiPO4 reported two structural phases appearing at high pressures, the so-called phases IV and V [M. Bykov et al., Angew. Chem. Int. Ed. 55, 15053 (2016).]. The latter was shown to include the first example of fivefold O-coordinated P atoms in an inorganic phosphate compound. In this work, we characterize the electronic structure and other physical properties of these phases by means of ab initio calculations and investigate the structural transition. We find that the appearance of phases IV and V coincides with a collapse of the Mott insulating gap and quenching of magnetism in phase III as pressure is applied. Remarkably, our calculations show that in the high-pressure phase V, these features reappear, leading to an antiferromagnetic Mott insulating phase, with robust local moments.</p>","","","","","","","","","","","","","2019-07-16","2019-07-16","2020-03-17","http://liu.diva-portal.org/smash/get/diva2:1337600/FULLTEXT01.pdf","","6","","2","urn:nbn:se:liu:diva-164113","","","","245132","false","","",""
"1360046","Johansson, Magnus [magjo23] [0000-0001-6708-1560] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Beličev, Petra P (University of Belgrade, Serbia);Gligorić, Goran (University of Belgrade, Serbia);Gulevich, Dmitry R. ( ITMO University, Russia);Skryabin, Dmitry V. (University of Bath, UK)","Nonlinear gap modes and compactons in a lattice model for spin-orbit coupled exciton-polaritons in zigzag chains","Artikel i tidskrift","Refereegranskat","eng","Journal of Physics Communications","2399-6528","","published","3","1","","1","17","2019","","","","Institute of Physics Publishing (IOPP)","","","","","","","10.1088/2399-6528/aaf7c9","000462249600003","","","urn:nbn:se:liu:diva-160854","","","nonlinear localized modes;exciton-polaritons;spin–orbit coupling;zigzag chain","Fysik (103)","","","","<p>We consider a system of generalized coupled Discrete Nonlinear Schrödinger (DNLS) equations, derived as a tight-binding model from the Gross-Pitaevskii-type equations describing a zigzag chain of weakly coupled condensates of exciton-polaritons with spin-orbit (TE-TM) coupling. We focus on the simplest case when the angles for the links in the zigzag chain are ±π/4 with respect to the chain axis, and the basis (Wannier) functions are cylindrically symmetric (zero orbital angular momenta). We analyze the properties of the fundamental nonlinear localized solutions, with particular interest in the discrete gap solitons appearing due to the simultaneous presence of spin–orbit coupling and zigzag geometry, opening a gap in the linear dispersion relation. In particular, their linear stability is analyzed. We also find that the linear dispersion relation becomes exactly flat at particular parameter values, and obtain corresponding compact solutions localized on two neighboring sites, with spin-up and spin-down parts π/2 out of phase at each site. The continuation of these compact modes into exponentially decaying gap modes for generic parameter values is studied numerically, and regions of stability are found to exist in the lower or upper half of the gap, depending on the type of gap modes.</p>","","","","","","","","","","","","","2019-10-10","2019-10-10","2020-03-25","http://liu.diva-portal.org/smash/get/diva2:1360046/FULLTEXT01.pdf","EU, Horisont 2020 [691011];Vetenskapsrådet [348-2013-6752]","5","","0","","","","","015001","false","true","",""
"1353569","Sangiovanni, Davide [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Ruhr Univ Bochum, Germany);Klarbring, Johan [johkl85] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Smirnova, D. (Ruhr Univ Bochum, Germany; Russian Acad Sci, Russia);Skripnyak, Natalia [natsk33] [0000-0003-1634-5882] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Gambino, Davide [davga91] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Mrovec, M. (Ruhr Univ Bochum, Germany);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Superioniclike Diffusion in an Elemental Crystal: bcc Titanium","Artikel i tidskrift","Refereegranskat","eng","Physical Review Letters","0031-9007","1079-7114","published","123","10","","","","2019","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevLett.123.105501","000483587200007","","","urn:nbn:se:liu:diva-160393","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Olle Engkvist Foundation; Swedish Research Council (VR) [2015-04391, 2014-4750]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFOMat-LiU) [2009-00971]; VINN Excellence Center Functional Nanoscale Materials (FunMat-2) [2016-05156]</p>","<p>Recent theoretical investigations [A. B. Belonoshko et aL Nat. Geosci. 10, 312 (2017)] revealed the occurrence of the concerted migration of several atoms in bcc Fe at inner-core temperatures and pressures. Here, we combine first-principles and semiempirical atomistic simulations to show that a diffusion mechanism analogous to the one predicted for bcc iron at extreme conditions is also operative and of relevance for the high-temperature bcc phase of pure Ti at ambient pressure. The mechanism entails a rapid collective movement of numerous (from two to dozens) neighbors along tangled closed-loop paths in defect-free crystal regions. We argue that this phenomenon closely resembles the diffusion behavior of superionics and liquid metals. Furthermore, we suggest that concerted migration is the atomistic manifestation of vanishingly small co-mode phonon frequencies previously detected via neutron scattering and the mechanism underlying anomalously large and markedly non-Arrhenius self-diffusivities characteristic of bcc Ti.</p>","","","","","","","","","","","","","2019-09-23","2019-09-23","2020-04-21","http://liu.diva-portal.org/smash/get/diva2:1353569/FULLTEXT01.pdf","","8","","2","urn:nbn:se:liu:diva-165270","","","","105501","false","","",""
"1302143","Klarbring, Johan [johkl85] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Low-energy paths for octahedral tilting in inorganic halide perovskites","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","99","10","","","","2019","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.99.104105","000461955500001","","","urn:nbn:se:liu:diva-156096","","","","Annan fysik (10399)","","","<p>Funding Agencies|Swedish Research Council (VR) [2014-4750]; Centre in Nano Science and Nano Technology (CeNano) at Linkoping University</p>","<p>Instabilities relating to cooperative octahedral tilting is common in materials with perovskite structures, in particular in the subclass of halide perovskites. In this work the energetics of octahedral tilting in the inorganic metal halide perovskites CsPbI3 and CsSnI3 are investigated using first-principles density functional theory calculations. Several low-energy paths between symmetry equivalent variants of the stable orthorhombic (Pnma) perovskite variant are identified and investigated. The results are in favor of the presence of dynamic disorder in the octahedral tilting phase transitions of inorganic halide perovskites. In particular, one specific type of path, corresponding to an out-of-phase ""tilt switch,"" is found to have significantly lower energy barrier than the others, which indicates the existence of a temperature range where the dynamic fluctuations of the octahedra follow only this type of path. This could produce a time averaged structure corresponding to the intermediate tetragonal (P4/mbm) structure observed in experiments. Deficiencies of the commonly employed simple one-dimensional ""double-well"" potentials in describing the dynamics of the octahedra are pointed out and discussed.</p>","","","","","","","","","","","","","2019-04-03","2019-04-03","2020-05-06","http://liu.diva-portal.org/smash/get/diva2:1302143/FULLTEXT01.pdf","","1","","2","urn:nbn:se:liu:diva-165554","","","","104105","false","","",""
"1380350","Miao, Kevin C. (Univ Chicago, IL 60637 USA);Bourassa, Alexandre (Univ Chicago, IL 60637 USA);Anderson, Christopher P. (Univ Chicago, IL 60637 USA);Whiteley, Samuel J. (Univ Chicago, IL 60637 USA);Crook, Alexander L. (Univ Chicago, IL 60637 USA);Bayliss, Sam L. (Univ Chicago, IL 60637 USA);Wolfowicz, Gary (Univ Chicago, IL 60637 USA);Thiering, Gergo (Hungarian Acad Sci, Hungary);Udvarhelyi, Peter (Hungarian Acad Sci, Hungary; Eotvos Lorand Univ, Hungary);Ivády, Viktor [vikiv58] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Hungarian Acad Sci, Hungary);Abe, Hiroshi (Natl Inst Quantum and Radiol Sci and Technol, Japan);Ohshima, Takeshi (Natl Inst Quantum and Radiol Sci and Technol, Japan);Gali, Adam (Hungarian Acad Sci, Hungary; Budapest Univ Technol and Econ, Hungary);Awschalom, David D. (Univ Chicago, IL 60637 USA; Univ Chicago, IL 60637 USA; Argonne Natl Lab, IL 60439 USA; Argonne Natl Lab, IL 60439 USA)","Electrically driven optical interferometry with spins in silicon carbide","Artikel i tidskrift","Refereegranskat","eng","Science Advances","","2375-2548","published","5","11","","","","2019","","","","AMER ASSOC ADVANCEMENT SCIENCE","","","","","","","10.1126/sciadv.aay0527","000499736100090","31803839","","urn:nbn:se:liu:diva-162763","","","","Atom- och molekylfysik och optik (10302)","","","<p>Funding Agencies|AFOSRUnited States Department of DefenseAir Force Office of Scientific Research (AFOSR) [FA9550-14-1-0231, FA9550-15-1-0029]; DARPAUnited States Department of DefenseDefense Advanced Research Projects Agency (DARPA) [D18AC00015KK1932]; NSF EFRINational Science Foundation (NSF) [EFMA-1641099]; ONROffice of Naval Research [N00014-17-1-3026]; National Research, Development and Innovation Office in Hungary (NKFIH) [2017-1.2.1-NKP2017-00001, NVKP 16-1-2016-0043, NN127902, KKP129866]; EU Commission (ASTERIQS project) [820394]; MTA Premium Postdoctoral Research Program; Knut and Alice Wallenberg Foundation through WBSQD2 project [2018.0071]; JSPS KAKENHIMinistry of Education, Culture, Sports, Science and Technology, Japan (MEXT)Japan Society for the Promotion of ScienceGrants-in-Aid for Scientific Research (KAKENHI) [17H01056, 18H03770]; Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource, a node of the NSFs National Nanotechnology Coordinated Infrastructure [NSF ECCS1542205]</p>","<p>Interfacing solid-state defect electron spins to other quantum systems is an ongoing challenge. The ground-state spins weak coupling to its environment not only bestows excellent coherence properties but also limits desired drive fields. The excited-state orbitals of these electrons, however, can exhibit stronger coupling to phononic and electric fields. Here, we demonstrate electrically driven coherent quantum interference in the optical transition of single, basally oriented divacancies in commercially available 4H silicon carbide. By applying microwave frequency electric fields, we coherently drive the divacancys excited-state orbitals and induce Landau-Zener-Stuckelberg interference fringes in the resonant optical absorption spectrum. In addition, we find remarkably coherent optical and spin subsystems enabled by the basal divacancys symmetry. These properties establish divacancies as strong candidates for quantum communication and hybrid system applications, where simultaneous control over optical and spin degrees of freedom is paramount.</p>","","","","","","","","","","","","","2019-12-18","2019-12-18","2020-06-05","http://liu.diva-portal.org/smash/get/diva2:1380350/FULLTEXT01.pdf","","14","","1","","","","","eaay0527","false","","",""
"1343872","Laniel, Dominique (Univ Bayreuth, Germany);Bykov, Maxim (Univ Bayreuth, Germany);Fedotenko, Timofey (Univ Bayreuth, Germany);Ponomareva, Alena V. (Natl Univ Sci and Technol MISIS, Russia);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Glazyrin, Konstantin (DESY, Germany);Svitlyk, Volodymyr (European Synchrotron Radiat Facil, France);Dubrovinsky, Leonid (Univ Bayreuth, Germany);Dubrovinskaia, Natalia (Univ Bayreuth, Germany)","High Pressure Investigation of the S-N-2 System up to the Megabar Range: Synthesis and Characterization of the SN2 Solid","Artikel i tidskrift","Refereegranskat","eng","Inorganic Chemistry","0020-1669","1520-510X","published","58","14","","9195","9204","2019","","","","AMER CHEMICAL SOC","","","","","","","10.1021/acs.inorgchem.9b00830","000475838000037","31247816","","urn:nbn:se:liu:diva-159727","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|Alexander von Humboldt Foundation; Federal Ministry of Education and Research, Germany (BMBF) [5K16WC1]; Deutsche Forschungsgemeinschaft (DFG) [DU 954-11/1, DU 393-9/2, DU 393-13/1]; Russian Science Foundation [18-12-00492]; Swedish Research Council (VR) [2015-04391]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]</p>","<p>Sulfur and nitrogen represent one of the most studied inorganic binary systems at ambient pressure on account of their large wealth of metastable exotic ring-like compounds. Under high pressure conditions, however, their behavior is unknown. Here, sulfur and nitrogen were compressed in a diamond anvil cell up to about 120 GPa and laser-heated at regular pressure intervals in an attempt to stabilize novel sulfur nitrogen compounds. Above 64 GPa, an orthorhombic (space group Pnnm) SN2 compound was synthesized and characterized by single-crystal and powder X-ray diffraction as well as Raman spectroscopy. It is shown to adopt a CaCl2-type structure hence it is isostructural, isomassic, and isoelectronic to CaCl2-type SiO2 comprised of SN6 octahedra. Complementary theoretical calculations were performed to provide further insight into the physicochemical properties of SN2, notably its equation of state, the bonding type between its constitutive elements, and its electronic density of states. This new solid is shown to be metastable down to about 20 GPa, after which it spontaneously decomposes into S and N-2. This investigation shows that despite the many metastable S N compounds existing at ambient conditions, none of them are formed by pressure.</p>","","","","","","","","","","","","","2019-08-19","2019-08-19","2020-06-11","","","9","","2","","","","","","false","","",""
"1333826","Jamnig, Andreas [andja71] [0000-0003-2765-2271] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Nanodesign [16854]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Poitiers, France);Sangiovanni, Davide Giuseppe [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Ruhr Univ Bochum, Germany);Abadias, G. (Univ Poitiers, France);Sarakinos, Kostas [kossa66] [0000-0003-2864-9509] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Nanodesign [16854]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Atomic-scale diffusion rates during growth of thin metal films on weakly-interacting substrates","Artikel i tidskrift","Refereegranskat","eng","Scientific Reports","2045-2322","2045-2322","published","9","","","","","2019","","","","Nature Publishing Group","","","","","","","10.1038/s41598-019-43107-8","000466127100065","31036908","2-s2.0-85065068804","urn:nbn:se:liu:diva-158369","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|French Government program ""Investissements dAvenir"" (LABEX INTERACTIFS) [ANR-11-LABX-0017-01]; Linkoping University (""LiU Career Contract"") [Dnr-LiU-2015-01510]; Swedish research council [VR-2015-04630]; Olle Engkvist foundation [SOEB 190-312]; Olle Engkvist Foundation</p>","<p>We use a combined experimental and theoretical approach to study the rates of surface diffusion processes that govern early stages of thin Ag and Cu film morphological evolution on weakly-interacting amorphous carbon substrates. Films are deposited by magnetron sputtering, at temperatures T-S between 298 and 413 K, and vapor arrival rates F in the range 0.08 to 5.38 monolayers/s. By employing in situ and real-time sheet-resistance and wafer-curvature measurements, we determine the nominal film thickness Theta at percolation (Theta(perc)) and continuous film formation (Theta(cont)) transition. Subsequently, we use the scaling behavior of Theta(perc) and Theta(cont) as a function of F and T-s, to estimate, experimentally, the temperature-dependent diffusivity on the substrate surface, from which we calculate Ag and Cu surface migration energy barriers E-D(exp) and attempt frequencies nu(exp)(0). By critically comparing E-D(exp) and nu(exp)(0) with literature data, as well as with results from our ab initio molecular dynamics simulations for single Ag and Cu adatom diffusion on graphite surfaces, we suggest that: (i) E-D(exp) and nu(exp)(0) correspond to diffusion of multiatomic clusters, rather than to diffusion of monomers; and (ii) the mean size of mobile clusters during Ag growth is larger compared to that of Cu. The overall results of this work pave the way for studying growth dynamics in a wide range of technologically-relevant weakly-interacting film/substrate systems-including metals on 2D materials and oxides-which are building blocks in next-generation nanoelectronic, optoelectronic, and catalytic devices.</p>","","","","","","","","","","","","","2019-07-02","2019-07-02","2020-08-24","http://liu.diva-portal.org/smash/get/diva2:1333826/FULLTEXT01.pdf","","4","","1","urn:nbn:se:liu:diva-168458","","","","6640","true","true","",""
"1337601","Monteseguro, V (Univ Valencia, Spain; European Radiat Synchrotron Facil, France);Sans, J. A. (Univ Politecn Valencia, Spain);Cuartero, V (European Radiat Synchrotron Facil, France; Ctr Univ Def Zaragoza, Spain);Cova, F. (European Radiat Synchrotron Facil, France);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia);Olovsson, Weine [weiol14] [0000-0002-2904-0108] (Linköpings universitet [276], Tekniska fakulteten [872902]) (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]);Popescu, C. (ALBA CELLS, Spain);Pascarelli, S. (European Radiat Synchrotron Facil, France);Garbarino, G. (European Radiat Synchrotron Facil, France);Jönsson, Johan [johjo06] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Irifune, T. (Ehime Univ, Japan; Tokyo Inst Technol, Japan);Errandonea, D. (Univ Valencia, Spain)","Phase stability and electronic structure of iridium metal at the megabar range","Artikel i tidskrift","Refereegranskat","eng","Scientific Reports","2045-2322","2045-2322","published","9","","","","","2019","","","","Nature Publishing Group","","","","","","","10.1038/s41598-019-45401-x","000472137700036","31222067","2-s2.0-85067628529","urn:nbn:se:liu:diva-158862","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Spanish Ministry of Science, Innovation and Universities; Spanish Research Agency (AEI); European Fund for Regional Development (FEDER) [MAT2016-75586-C4-1/2-P]; Generalitat Valenciana [Prometeo/2018/123]; Spanish Mineco Project [FIS2017-83295-P]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; Ministry of Science and High Education of the Russian Federation [K2-2019-001]; ""Juan de la Cierva"" fellowship [FJCI-2016-27921]; ""Ramon y Cajal"" fellowship [RYC-2015-17482]</p>","<p>The 5d transition metals have attracted specific interest for high-pressure studies due to their extraordinary stability and intriguing electronic properties. In particular, iridium metal has been proposed to exhibit a recently discovered pressure-induced electronic transition, the so-called core-level crossing transition at the lowest pressure among all the 5d transition metals. Here, we report an experimental structural characterization of iridium by x-ray probes sensitive to both long- and short-range order in matter. Synchrotron-based powder x-ray diffraction results highlight a large stability range (up to 1.4 Mbar) of the low-pressure phase. The compressibility behaviour was characterized by an accurate determination of the pressure-volume equation of state, with a bulk modulus of 339(3) GPa and its derivative of 5.3(1). X-ray absorption spectroscopy, which probes the local structure and the empty density of electronic states above the Fermi level, was also utilized. The remarkable agreement observed between experimental and calculated spectra validates the reliability of theoretical predictions of the pressure dependence of the electronic structure of iridium in the studied interval of compressions.</p>","","","","","","","","","","","","","2019-07-16","2019-07-16","2020-09-15","http://liu.diva-portal.org/smash/get/diva2:1337601/FULLTEXT01.pdf","","12","","1","urn:nbn:se:liu:diva-164113","","","","8940","true","true","",""
"1306525","Olovsson, Weine [weiol14] [0000-0002-2904-0108] (Linköpings universitet [276], Tekniska fakulteten [872902]) (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]);Mizoguchi, Teruyasu (Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan);Magnuson, Martin [marma66] [0000-0002-0317-0190] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Kontur, Stefan (Physics Department and IRIS Adlershof, Humboldt-Universität zu Berlin, Zum Großen Windkanal 6, 12489 Berlin, Germany);Hellman, Olle (Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467, United States / Department of Applied Physics and Materials Science, California Institute of Technology, Pasadena, California 91125, United States);Tanaka, Isao (Department of Materials Science and Engineering, Kyoto University, Sakyo, Kyoto 606-8501, Japan);Draxl, Claudia (Physics Department and IRIS Adlershof, Humboldt-Universität zu Berlin, Zum Großen Windkanal 6, 12489 Berlin, Germany / European Theoretical Spectroscopy Facility (ETSF)","Vibrational Effects in X-ray Absorption Spectra of Two-Dimensional Layered Materials","Artikel i tidskrift","Refereegranskat","eng","The Journal of Physical Chemistry C","1932-7447","1932-7455","published","123","15","","9688","9692","2019","","","","ACS Publications","","","","","","","10.1021/acs.jpcc.9b00179","000465488600005","","","urn:nbn:se:liu:diva-156490","","","","Fysik (103)","","","<p>Funding agencies: Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; Knut and Alice Wallenbergs Foundation; Swedish Energy Research [43606-1]; Carl Trygger Foundation [CTS16:303, CTS14:310]; JSPS KA</p>","<p>With the examples of the C K-edge in graphite and the B K-edge in hexagonal boron nitride, we demonstrate the impact of vibrational coupling and lattice distortions on the X-ray absorption near-edge structure (XANES) in two-dimensional layered materials. Theoretical XANES spectra are obtained by solving the Bethe–Salpeter equation of many-body perturbation theory, including excitonic effects through the correlated motion of the core hole and excited electron. We show that accounting for zero-point motion is important for the interpretation and understanding of the measured X-ray absorption fine structure in both materials, in particular for describing the σ*-peak structure.</p>","","","","","","","","","","","","","2019-04-24","2019-04-24","2020-09-15","http://liu.diva-portal.org/smash/get/diva2:1306525/FULLTEXT01.pdf","","7","","1","","","","","","true","","",""
"1276262","Mockuté, Aurelija [aurmo58] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Palisaitis, Justinas [juspa01] [0000-0003-3203-7935] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Nedfors, Nils [nilne07] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Berastegui, P. (Uppsala Univ, Sweden);Broitman, Esteban [broes27] [0000-0003-3277-1945] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (SKF Res and Technol Dev Ctr, Netherlands);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Näslund, Lars-Åke [larna84] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Hultman, Lars [larhu75] [0000-0002-2837-3656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Patscheider, J. (Evatec AG, Switzerland);Jansson, U. (Uppsala Univ, Sweden);Persson, Per O A [perpe25] [0000-0001-9140-6724] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Rosén, Johanna [johro07] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Synthesis and characterization of (Ti1-xAlx)B2+Delta thin films from combinatorial magnetron sputtering","Artikel i tidskrift","Refereegranskat","eng","Thin Solid Films","0040-6090","1879-2731","published","669","","","181","187","2019","","","","ELSEVIER SCIENCE SA","","","","","","","10.1016/j.tsf.2018.10.042","000453405600026","","","urn:nbn:se:liu:diva-153652","","","Titanium aluminium diboride; Thin films; Combinatorial sputtering; Mechanical properties; Phase decomposition","Keramteknik (20501)","","","<p>Funding Agencies|Knut and Alice Wallenbergs (KAW) Foundation [KAW 2015.0043]; Swedish Research Council [330-2014-6336, 2016-04412, 642-2013-8020]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; Marie Sklodowska Curie Actions COFUND [INCA 600398]; Swedish Foundation for Strategic Research; Research Infrastructure Fellow Program [RIF 14-0074]; KAW Foundation</p>","<p>(Ti1-xAlx)B2+Delta films with a lateral composition gradient of x = [0.30-0.66] and Delta = [0.07-1.22] were deposited on an Al2O3 wafer by dual magnetron sputtering at 400 degrees C from sintered TiB2 and AlB2 targets. Composition analysis indicates that higher Ti:Al ratios favor overstoichiometry in B and a reduced incorporation of O. Transmission electron microscopy reveals distinctly different microstructures of Ti- and Al-rich compositions, with formation of characteristic conical growth features for the latter along with a lower degree of crystallinity and significantly less tissue phase from B segregation at the grain boundaries. For Al-rich films, phase separation into Ti- and Al-rich diboride nanometer-size domains is observed and interpreted as surface-initiated spinodal decomposition. The hardness of the films ranges from 14 to 28 GPa, where the higher values were obtained for the Ti-rich regions of the metal boride.</p>","","","","","","","","","","","","","2019-01-07","2019-01-07","2020-10-26","http://liu.diva-portal.org/smash/get/diva2:1276262/FULLTEXT01.pdf","","12","","1","","","","","","false","","",""
"1382238","Filippov, Stanislav [stafi86] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Stockholm Univ, Sweden);Grinderslev, Jakob B. (Aarhus Univ, Denmark);Andersson, Mikael S. (Chalmers Univ Technol, Sweden);Armstrong, Jeff (Rutherford Appleton Lab, England);Karlsson, Maths (Chalmers Univ Technol, Sweden);Jensen, Torben R. (Aarhus Univ, Denmark);Klarbring, Johan [johkl85] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Haussermann, Ulrich (Stockholm Univ, Sweden)","Analysis of Dihydrogen Bonding in Ammonium Borohydride","Artikel i tidskrift","Refereegranskat","eng","The Journal of Physical Chemistry C","1932-7447","1932-7455","published","123","47","","28631","28639","2019","","","","AMER CHEMICAL SOC","","","","","","","10.1021/acs.jpcc.9b08968","000500417600013","","","urn:nbn:se:liu:diva-162885","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|Nordforsk within the project FunHy; Swedish research council (VR)Swedish Research Council; Carl Tryggers Stiftelse (CTS) for Vetenskaplig Forskning; Swedish Government Strategic Research Area in Materials Science on Advanced Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]</p>","<p>The structural and vibrational properties of ammonium borohydride, NH4BH4, have been examined by first-principles density functional theory (DFT) calculations and inelastic neutron scattering (INS). The H disordered crystal structure of NH4BH4 is composed of the tetrahedral complex ions NH4+ and BH4-, which are arranged as in the fcc NaCl structure and linked by intermolecular dihydrogen bonding. Upon cooling, the INS spectra revealed a structural transition between 45 and 40 K. The reversible transition occurs upon heating between 46 and 49 K. In the low-temperature form reorientational dynamics are frozen. The libration modes for BH4- and NH4+ are near 300 and 200 cm(-1), respectively. Upon entering the fcc high-temperature form, NH4+ ions attain fast reorientational dynamics, as indicated in the disappearance of the NH4+ libration band, whereas BH4- ions become significantly mobile only at temperatures above 100 K. The vibrational behavior of BH4- ions in NH4BH4 compares well to the heavier alkali metal borohydrides, NaBH4-CsBH4. DFT calculations revealed a nondirectional nature of the dihydrogen bonding in NH4BH4 with only weak tendency for long-range order. Different rotational configurations of complex ions appear quasi-degenerate, which is reminiscent of glasses.</p>","","","","","","","","","","","","","2020-01-02","2020-01-02","2020-11-04","http://liu.diva-portal.org/smash/get/diva2:1382238/FULLTEXT01.pdf","","9","","1","","","","","","false","","",""
"1283673","Vorotilo, S. (Natl Univ Sci and Technol MISIS, Russia);Sidnov, K. (Natl Univ Sci and Technol MISIS, Russia; Russian Acad Sci, Russia);Mosyagin, I. Yu (Natl Univ Sci and Technol MISIS, Russia);Khvan, A. V (Natl Univ Sci and Technol MISIS, Russia);Levashov, E. A. (Natl Univ Sci and Technol MISIS, Russia);Patsera, E. I (Natl Univ Sci and Technol MISIS, Russia);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia)","Ab-initio modeling and experimental investigation of properties of ultra-high temperature solid solutions TaxZr1-xC","Artikel i tidskrift","Refereegranskat","eng","Journal of Alloys and Compounds","0925-8388","1873-4669","published","778","","","480","486","2019","","","","ELSEVIER SCIENCE SA","","","","","","","10.1016/j.jallcom.2018.11.219","000455179500053","","","urn:nbn:se:liu:diva-154089","","","UHTC; Phase diagram; DFT; SHS; Annealing","Metallurgi och metalliska material (20506)","","","<p>Funding Agencies|Ministry of Education and Science of the Russian Federation [14.Y26.31.0005, K2-2017-080]; Russian Science Foundation [17-79-10173]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]</p>","<p>Due to their high melting temperature, high-temperature oxidation resistance and outstanding mechanical properties, TaxZr1-xC solid solutions are promising ultra-high temperature ceramics (UHTC). However, accelerated knowledge-based development of UHTCs solid solutions requires reliable data regarding the properties of the solution phases in the whole interval of concentrations. At present, there are contradictory reports regarding the existence of the miscibility gap in Ta-Zr-C system at temperatures below 900 degrees C. In this work, we carry out ab-initio calculations of the thermodynamic properties of TaxZr1-xC alloys and demonstrate that the solid solutions should not decompose into TaC and ZrC end member compounds. We synthesize single-phase samples of TaxZr1-xC with compositions x = 0.9, 0.8, 0.6, and 0.3 by self-propagating high-temperature synthesis (SHS) and anneal the samples for 40 h. We do not observe any sign of the decomposition of the solid solution during the annealing, corroborating the conclusions obtained by theoretical simulations. (C) 2018 Elsevier B.V. All rights reserved.</p>","","","","","","","","","","","","","2019-01-29","2019-01-29","2020-11-19","http://liu.diva-portal.org/smash/get/diva2:1283673/FULLTEXT01.pdf","","7","","1","","","","","","false","","",""
"1376520","Eklof, Daniel (Stockholm Univ, Sweden);Fischer, Andreas (Augsburg Univ, Germany);Ektarawong, Annop (Chulalongkorn Univ, Thailand; Commiss Higher Educ, Thailand);Jaworski, Aleksander (Stockholm Univ, Sweden);Pell, Andrew J. (Stockholm Univ, Sweden);Grins, Jekabs (Stockholm Univ, Sweden);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Wu, Yang (Tsinghua Univ, Peoples R China);Widom, Michael (Carnegie Mellon Univ, PA 15213 USA);Scherer, Wolfgang (Augsburg Univ, Germany);Haussermann, Ulrich (Stockholm Univ, Sweden)","Mysterious SiB3: Identifying the Relation between alpha- and beta-SiB3","Artikel i tidskrift","Refereegranskat","eng","ACS Omega","","2470-1343","published","4","20","","18741","18759","2019","","","","AMER CHEMICAL SOC","","","","","","","10.1021/acsomega.9b02727","000496814700031","31737836","","urn:nbn:se:liu:diva-162525","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|Swedish Research CouncilSwedish Research Council [2016-03441]; National Science FoundationNational Science Foundation (NSF) [DMR-1007557]; Deutsche ForschungsgemeinschaftGerman Research Foundation (DFG) [SCHE 487/12-1]; U.S. Department of EnergyUnited States Department of Energy (DOE) [DE-SC0014506]; Ratchadaphiseksomphot Endowment Fund, Chulalongkorn UniversityChulalongkorn University; Swedish Foundation for Strategic Research (SSF) through the Future Research Leaders program; Swedish Government Strategic Research Area in Materials Science on Advanced Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]</p>","<p>Binary silicon boride SiB3 has been reported to occur in two forms, as disordered and nonstoichiometric alpha-SiB3-x, which relates to the alpha-rhombohedral phase of boron, and as strictly ordered and stoichiometric beta-SiB3. Similar to other boron-rich icosahedral solids, these SiB3 phases represent potentially interesting refractory materials. However, their thermal stability, formation conditions, and thermodynamic relation are poorly understood. Here, we map the formation conditions of alpha-SiB3-x and beta-SiB3 and analyze their relative thermodynamic stabilities. alpha-SiB3-x is metastable (with respect to beta-SiB3 and Si), and its formation is kinetically driven. Pure polycrystalline bulk samples may be obtained within hours when heating stoichiometric mixtures of elemental silicon and boron at temperatures 1200-1300 degrees C. At the same time, alpha-SiB3-x decomposes into SiB6 and Si, and optimum time-temperature synthesis conditions represent a trade-off between rates of formation and decomposition. The formation of stable beta-SiB3 was observed after prolonged treatment (days to weeks) of elemental mixtures with ratios Si/B = 1:11:4 at temperatures 1175-1200 degrees C. The application of high pressures greatly improves the kinetics of SiB3 formation and allows decoupling of SiB3 formation from decomposition. Quantitative formation of beta-SiB3 was seen at 1100 degrees C for samples pressurized to 5.5-8 GPa. beta-SiB3 decomposes peritectoidally at temperatures between 1250 and 1300 degrees C. The highly ordered nature of beta-SiB3 is reflected in its Raman spectrum, which features narrow and distinct lines. In contrast, the Raman spectrum of alpha-SiB3-x is characterized by broad bands, which show a clear relation to the vibrational modes of isostructural, ordered B6P. The detailed composition and structural properties of disordered alpha-SiB3-x were ascertained by a combination of single-crystal X-ray diffraction and Si-29 magic angle spinning NMR experiments. Notably, the compositions of polycrystalline bulk samples (obtained at T amp;lt;= 1200 degrees C) and single crystal samples (obtained from Si-rich molten Si-B mixtures at T amp;gt; 1400 degrees C) are different, SiB2.93(7) and SiB2.64(2), respectively. The incorporation of Si in the polar position of B-12 icosahedra results in highly strained cluster units. This disorder feature was accounted for in the refined crystal structure model by splitting the polar position into three sites. The electron-precise composition of alpha-SiB3-x is SiB2.5 and corresponds to the incorporation of, on average, two Si atoms in each B-12 icosahedron. Accordingly, alpha-SiB3-x constitutes a mixture of B10Si2 and B11Si clusters. The structural and phase stability of alpha-SiB3-x were explored using a first-principles cluster expansion. The most stable composition at 0 K is SiB2.5, which however is unstable with respect to the decomposition beta-SiB3 + Si. Modeling of the configurational and vibrational entropies suggests that alpha-SiB3-x only becomes more stable than beta-SiB3 at temperatures above its decomposition into SiB6 and Si. Hence, we conclude that alpha-SiB3-x is metastable at all temperatures. Density functional theory electronic structure calculations yield band gaps of similar size for electron-precise alpha-SiB2.5 and beta-SiB3, whereas alpha-SiB3 represents a p-type conductor.</p>","","","","","","","","","","","","","2019-12-09","2019-12-09","2020-12-15","http://liu.diva-portal.org/smash/get/diva2:1376520/FULLTEXT01.pdf","","12","","1","","","","","","false","","",""
"1367938","Mei, Antonio B. (Cornell Univ, NY 14853 USA; Univ Illinois, IL 61801 USA; Univ Illinois, IL 61801 USA);Miao, Ludi (Cornell Univ, NY 14853 USA);Wahila, Matthew J. (Binghamton Univ, NY 13902 USA);Khalsa, Guru (Cornell Univ, NY 14853 USA);Wang, Zhe (Cornell Univ, NY 14853 USA);Barone, Matthew (Cornell Univ, NY 14853 USA);Schreiber, Nathaniel J. (Cornell Univ, NY 14853 USA);Noskin, Lindsey E. (Cornell Univ, NY 14853 USA);Paik, Hanjong (Cornell Univ, NY 14853 USA);Tiwald, Thomas E. (JA Woollam Co, NE 68508 USA);Zheng, Qiye (Univ Illinois, IL 61801 USA; Lawrence Berkeley Natl Lab, CA 94720 USA; Univ Calif Berkeley, CA 94720 USA);Haasch, Richard T. (Univ Illinois, IL 61801 USA);Sangiovanni, Davide [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Ruhr Univ Bochum, Germany);Piper, Louis F. J. (Binghamton Univ, NY 13902 USA);Schlom, Darrell G. (Cornell Univ, NY 14853 USA; Kavli Inst Cornell Nanoscale Sci, NY 14853 USA)","Adsorption-controlled growth and properties of epitaxial SnO films","Artikel i tidskrift","Refereegranskat","eng","Physical Review Materials","","2475-9953","published","3","10","","","","2019","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevMaterials.3.105202","000491267200005","","","urn:nbn:se:liu:diva-161608","","","","Materialkemi (10403)","","","<p>Funding Agencies|ASCENT - DARPA; National Science Foundation (NSF)National Science Foundation (NSF) [DGE-1650441]; NSF MRSEC ProgramNational Science Foundation (NSF)NSF - Directorate for Mathematical & Physical Sciences (MPS) [DMR-1719875]; NSFNational Science Foundation (NSF) [ECCS-1542081, DMR-0703406]; Air Force Office of Scientific ResearchUnited States Department of DefenseAir Force Office of Scientific Research (AFOSR) [FA955018-1-0024]; U.S. Department of Energy (DOE) Office of Science User FacilityUnited States Department of Energy (DOE) [DEAC02-06CH11357]; Olle Engkvist Foundation; NSF [Platform for the Accelerated Realization, Analysis, and Discovery of Interface Materials (PARADIM)] [DMR-1539918]</p>","<p>When it comes to providing the unusual combination of optical transparency, p-type conductivity, and relatively high mobility, Sn2+-based oxides are promising candidates. Epitaxial films of the simplest Sn2+ oxide, SnO, are grown in an adsorption-controlled regime at 380 degrees C on Al2O3 substrates by molecular-beam epitaxy, where the excess volatile SnOx desorbs from the film surface. A commensurately strained monolayer and an accompanying van der Waals gap is observed near the substrate interface, promoting layers with high structural perfection notwithstanding a large epitaxial lattice mismatch (-12%). The unintentionally doped films exhibit p-type conductivity with carrier concentration 2.5 x 10(16) cm(-3) and mobility 2.4 cm(2) V(-1)s(-1) at room temperature. Additional physical properties are measured and linked to the Sn2+ valence state and corresponding lone-pair charge-density distribution.</p>","","","","","","","","","","","","","2019-11-05","2019-11-05","2020-12-15","http://liu.diva-portal.org/smash/get/diva2:1367938/FULLTEXT01.pdf","","15","","1","","","","","105202","false","","",""
"1334874","Ektarawong, Annop [annek02] [0000-0002-6059-6833] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Chulalongkorn Univ, Thailand; Natl Univ Singapore, Singapore; Natl Univ Singapore, Singapore; Thailand Ctr Excellence Phys, Thailand);Feng, Y. P. (Natl Univ Singapore, Singapore);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Phase stability of two-dimensional monolayer As1-xPx solid solutions revealed by a first-principles cluster expansion","Artikel i tidskrift","Refereegranskat","eng","Physical Review Materials","","2475-9953","published","3","5","","","","2019","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevMaterials.3.054005","000470902100002","","","urn:nbn:se:liu:diva-158567","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|Swedish Research Council (VR) [2014-6336]; Marie Sklodowska Curie Actions, Cofund, Project [INCA 600398]; Swedish Foundation for Strategic Research (SSF) through the Future Research Leaders 6 programme; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; Kungl. Ingenjorsvetenskapsakademiens Hans Werthen-Fond</p>","<p>The phase stability of two-dimensional monolayer As1-xPx solid solutions, exhibiting the puckered (alpha phase) and buckled (beta phase) structures are investigated using a first-principles cluster-expansion method. Canonical Monte Carlo simulations, together with harmonic approximation, are performed to capture the influences of thermally induced configurational disorder and lattice vibrations on the phase stability of monolayer As1-xPx. We first demonstrate that, as the temperature approaches 0 K, the monolayer As1-xPx displays a tendency toward phase separation into its constituent elemental phases, and thus no stable ordered structures of As1-xPx, both alpha and beta phases, are predicted to be thermodynamically stable. We further reveal with the inclusion of the lattice vibrational contributions that beta-As1-xPx is thermodynamically favored over alpha-As1-xPx, across the entire composition range even at 0 K and increasingly so at higher temperature, and a continuous series of disordered solid solution of beta-As1-xPx, where 0 amp;lt;= x amp;lt;= 1, is predicted at the temperature above 550 K. These findings not only indicate that the ordered structures of monolayer alpha-As1-xPx, and beta-As1-xPx, frequently studied in the literature, may not exist in nature, but also presumably suggest that monolayer alpha-As1-xPx is metastable with respect to monolayer beta-As1-xPx.</p>","","","","","","","","","","","","","2019-07-03","2019-07-03","2020-12-15","http://liu.diva-portal.org/smash/get/diva2:1334874/FULLTEXT01.pdf","","3","","1","","","","","054005","false","","",""
"1297529","Filippov, Stanislav [stafi86] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Stockholm Univ, Sweden);Klarbring, Johan [johkl85] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Haussermann, Ulrich (Stockholm Univ, Sweden);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Temperature-induced phase transition and Li self-diffusion in Li2C2: A first-principles study","Artikel i tidskrift","Refereegranskat","eng","Physical Review Materials","","2475-9953","published","3","2","","","","2019","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevMaterials.3.023602","000459220000001","","","urn:nbn:se:liu:diva-155002","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|Swedish Research Council (VR) [2014-4750, 2014-3980]; Swedish Government Strategic Research Area in Materials Science on Advanced Functional Materials at Linkoping University [2009-00971]; Carl Tryggers Stiftelse (CTS) [16:198]</p>","<p>Lithium carbide, Li2C2, is a fascinating material that combines strong covalent and weak ionic bonding resulting in a wide range of unusual properties. The mechanism of its phase transition from the ground-state orthorhombic (Immm) to the high-temperature cubic (Fm (3) over barm) crystal structure is not well understood and here we elucidate it with help of first-principles calculations. We show that stabilization of the cubic phase is a result of a temperature-induced disorientation of the C-C dumbbells and their further thermal rotations. Due to these rotations rather large deviatoric stress, which is associated with the dumbbell alignment along one of the crystallographic axes, averages out making the cubic structure mechanically stable. At high temperature we observe a type-II superionic transition to a state of high Li self-diffusion involving collective ionic motion mediated by the formation of Frenkel pairs.</p>","","","","","","","","","","","","","2019-03-20","2019-03-20","2020-12-15","http://liu.diva-portal.org/smash/get/diva2:1297529/FULLTEXT01.pdf","","4","","1","","","","","023602","false","","",""
"1382358","Ivády, Viktor [vikiv58] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Wigner Res Ctr Phys, Hungary);Davidsson, Joel [joeda01] [0000-0002-5349-3318] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Delegan, Nazar (Argonne Natl Lab, IL USA; Argonne Natl Lab, IL USA);Falk, Abram L. (Univ Chicago, IL USA; IBM TJ Watson Res Ctr, NY USA);Klimov, Paul V. (Univ Chicago, IL USA);Whiteley, Samuel J. (Univ Chicago, IL USA);Hruszkewycz, Stephan O. (Argonne Natl Lab, IL USA);Holt, Martin V. (Argonne Natl Lab, IL USA);Heremans, F. Joseph (Argonne Natl Lab, IL USA; Univ Chicago, IL USA);Nguyen, Son Tien [nguso90] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Awschalom, David D. (Argonne Natl Lab, IL USA; Univ Chicago, IL USA);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia);Gali, Adam (Wigner Res Ctr Phys, Hungary; Budapest Univ Technol and Econ, Hungary)","Stabilization of point-defect spin qubits by quantum wells","Artikel i tidskrift","Refereegranskat","eng","Nature Communications","2041-1723","2041-1723","published","10","","","","","2019","","","","NATURE PUBLISHING GROUP","","","","","","","10.1038/s41467-019-13495-6","000502076500001","31811137","","urn:nbn:se:liu:diva-162948","","","","Annan fysik (10399)","","","<p>Funding Agencies|MTA Premium Postdoctoral Research Program; Knut and Alice Wallenberg Foundation through WBSQD2 project [2018.0071]; Swedish Government Strategic Research Areas in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; Swedish e-Science Centre (SeRC); Swedish Research CouncilSwedish Research Council [VR 2016-04068]; Carl-Trygger Stiftelse for Vetenskaplig Forskning [CTS 15:339]; Ministry of Education and Science of the Russian FederationMinistry of Education and Science, Russian Federation [K2-2019-001, 211]; Hungarian NKFIH grants of the National Excellence Program of Quantumcoherent materials project [KKP129866]; EU QuantERA Nanospin project [127902]; EU H2020 Quantum Technology Flagship project ASTERIQS [820394]; NVKP project [NVKP_16-1-2016-0043]; National Quantum Technology Program [2017-1.2.1-NKP-2017-00001]; U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Science and Engineering DivisionUnited States Department of Energy (DOE); DOE Office of ScienceUnited States Department of Energy (DOE) [DE-AC02-06CH11357]; Center for Nanoscale Materials, a U.S. Department of Energy Office of Science User FacilityUnited States Department of Energy (DOE) [DE-AC02-06CH11357]; DOE, Office of Basic Energy SciencesUnited States Department of Energy (DOE)</p>","<p>Defect-based quantum systems in wide bandgap semiconductors are strong candidates for scalable quantum-information technologies. However, these systems are often complicated by charge-state instabilities and interference by phonons, which can diminish spin-initialization fidelities and limit room-temperature operation. Here, we identify a pathway around these drawbacks by showing that an engineered quantum well can stabilize the charge state of a qubit. Using density-functional theory and experimental synchrotron X-ray diffraction studies, we construct a model for previously unattributed point defect centers in silicon carbide as a near-stacking fault axial divacancy and show how this model explains these defects robustness against photoionization and room temperature stability. These results provide a materials-based solution to the optical instability of color centers in semiconductors, paving the way for the development of robust single-photon sources and spin qubits.</p>","","","","","","","","","","","","","2020-01-02","2020-01-02","2021-02-08","http://liu.diva-portal.org/smash/get/diva2:1382358/FULLTEXT01.pdf","","13","","2","urn:nbn:se:liu:diva-173108","","","","5607","false","","",""
"1303228","Davidsson, Joel [joeda01] [0000-0002-5349-3318] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ivády, Viktor [vikiv58] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Hungarian Acad Sci, Hungary);Armiento, Rickard [ricar47] [0000-0002-5571-0814] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ohshima, Takeshi (Natl Inst Quantum and Radiol Sci and Technol, Japan);Nguyen, Son Tien [nguso90] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Gali, Adam (Hungarian Acad Sci, Hungary; Budapest Univ Technol and Econ, Hungary);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia)","Identification of divacancy and silicon vacancy qubits in 6H-SiC","Artikel i tidskrift","Refereegranskat","eng","Applied Physics Letters","0003-6951","1077-3118","published","114","11","","","","2019","","","","AMER INST PHYSICS","","","","","http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-165974","","10.1063/1.5083031","000462086600014","","","urn:nbn:se:liu:diva-156202","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Swedish e-Science Centre (SeRC); Swedish Government Strategic Research Areas in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; Swedish Research Council (VR) [2016-04068, 2016-04810]; Centre in Nano Science and Nanotechnology (CeNano); Carl Trygger Stiftelse for Vetenskaplig Forskning [CTS 15: 339]; JSPS KAKENHI [A 17H01056, 18H03770]; Ministry of Science and High Education of the Russian Federation [K2-2019-001, 211]; MTA Premium Postdoctoral Research Program; National Research Development and Innovation Office of Hungary (NKFIH) within the Quantum Technology National Excellence Program [2017-1.2.1-NKP-2017-00001]; National Research Development and Innovation Office of Hungary (NKFIH) within NVKP Program [NVKP 16-1-20160043]; National Research Development and Innovation Office of Hungary (NKFIH) within Excellent Researcher Program [KKP129886]; EU QuantERA Nanospin (NKFIH) [127902]</p>","<p>Point defects in semiconductors are relevant for use in quantum technologies as room temperature qubits and single photon emitters. Among suggested defects for these applications are the negatively charged silicon vacancy and the neutral divacancy in SiC. The possible nonequivalent configurations of these defects have been identified in 4H-SiC, but for 6H-SiC, the work is still in progress. In this paper, we identify the different configurations of the silicon vacancy and the divacancy defects to each of the V1-V3 and the QL1-QL6 color centers in 6H-SiC, respectively. We accomplish this by comparing the results from ab initio calculations with experimental measurements for the zero-phonon line, hyperfine tensor, and zero-field splitting. Published under license by AIP Publishing.</p>","","","","","","","","","","","","","2019-04-09","2019-04-09","2021-02-08","http://liu.diva-portal.org/smash/get/diva2:1303228/FULLTEXT01.pdf","","7","","2","urn:nbn:se:liu:diva-173108","","","","112107","false","","",""
"1337796","Khvan, A. V. (NUST MISIS, Russia);Babkina, T. (Lomonosov Moscow State Univ, Russia);Dinsdale, A. T. (Hampton Thermodynam Ltd, England);Uspenskaya, I. A. (Lomonosov Moscow State Univ, Russia);Fartushna, I. V. (NUST MISIS, Russia);Druzhinina, A. I. (Lomonosov Moscow State Univ, Russia);Syzdykova, A. B. (NUST MISIS, Russia);Belov, M. P. (NUST MISIS, Russia);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (NUST MISIS, Russia)","Thermodynamic properties of tin: Part I Experimental investigation, ab-initio modelling of alpha-, beta-phase and a thermodynamic description for pure metal in solid and liquid state from 0 K","Artikel i tidskrift","Refereegranskat","eng","Calphad","0364-5916","1873-2984","published","65","","","50","72","2019","","","","PERGAMON-ELSEVIER SCIENCE LTD","","","","","","","10.1016/j.calphad.2019.02.003","000470946700007","","","urn:nbn:se:liu:diva-158799","","","Tin; Two state liquid model; Expanded Einstein model; Ab-initio calculation; Adiabatic calorimetry","Metallurgi och metalliska material (20506)","","","<p>Funding Agencies|Ministry of Science and High Education of the Russian Federation [K2-2018-010]; [AAAA-A16-116061750195-2]</p>","<p>Thermodynamic data for crystalline white and grey tin were assessed using an extended Einstein model from 0 K. Ab-initio simulations in the framework of density functional theory (DFT) with the quasiharmonic approximation (QHA) were carried out to define the heat capacities for both phases of tin from 0 K up to room temperatures. Good agreement was observed between theoretical and experimental heat capacities, which makes it possible to combine theoretical and experimental data to determine the standard entropies. Data for the liquid phase were described using a two state model. During the assessment, careful analysis of the experimental data was carried out. In order to fulfil the need for a precise evaluation of S-298(o) we needed to use an additional technique using multiple Einstein functions, which allows the experimental heat capacity and enthalpy data for the solid phase to be approximated accurately from 0 K up to the melting point and to estimate solid phase transition entropy and enthalpy which are difficult to measure due to a high activation barrier. Additional measurements of heat capacity were carried out where existing data were scarce.</p>","","","","","","","","","","","","","2019-07-17","2019-07-17","2021-02-16","http://liu.diva-portal.org/smash/get/diva2:1337796/FULLTEXT01.pdf","","9","","1","","","","","","false","","",""
"1393931","Landälv, Ludvig [ludla97] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Sandvik Coromant AB, Sweden);Rogström, Lina [linro82] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Nanostrukturerade material [2221]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Lu, Jun [junlu07] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ostach, Daniel (Helmholtz Zentrum Geesthacht, Germany);Eriksson, Fredrik [freer90] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Junaid, Muhammad [junmu06] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ghafoor, Naureen [naugh16] [0000-0002-5828-5796] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ekström, Erik [eriek66] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Hsiao, Ching-Lien [chihs76] [0000-0001-7192-0670] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Leiste, Harald (Karlsruhe Inst Technol, Germany);Ahlgren, Mats (Sandvik Coromant AB, Sweden);Gothelid, Emmanuelle (Sandvik Coromant AB, Sweden);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Hultman, Lars [larhu75] [0000-0002-2837-3656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Stuber, Michael (Karlsruhe Inst Technol, Germany);Schell, Norbert (Helmholtz Zentrum Geesthacht, Germany);Birch, Jens [jenbi91] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Eklund, Per [perek02] [0000-0003-1785-0864] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Phase evolution of radio frequency magnetron sputtered Cr-rich (Cr,Zr)(2)O-3 coatings studied by in situ synchrotron X-ray diffraction during annealing in air or vacuum","Artikel i tidskrift","Refereegranskat","eng","Journal of Materials Research","0884-2914","2044-5326","published","34","22","","3735","3746","2019","","","","CAMBRIDGE UNIV PRESS","","","","","","","10.1557/jmr.2019.340","000510319300001","","","urn:nbn:se:liu:diva-163680","","","physical vapor deposition (PVD); annealing; oxide","Materialkemi (10403)","","","<p>Funding Agencies|Swedish Research Council (VR)Swedish Research Council [621-20124368, 330-2014-6336]; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; Marie Sklodowska Curie Actions, Cofund, Project INCA [600398]; Swedish Foundation for Strategic Research (SSF) through the Future Research Leaders 6 program; Swedish Research Council via the Rontgen Angstrom Cluster (RAC) Frame Program [2011-6505]; German Federal Ministry of Education and Research (BMBF)Federal Ministry of Education & Research (BMBF) [05K12CG1]</p>","<p>The phase evolution of reactive radio frequency (RF) magnetron sputtered Cr0.28Zr0.10O0.61 coatings has been studied by in situ synchrotron X-ray diffraction during annealing under air atmosphere and vacuum. The annealing in vacuum shows t-ZrO2 formation starting at similar to 750-800 degrees C, followed by decomposition of the alpha-Cr2O3 structure in conjunction with bcc-Cr formation, starting at similar to 950 degrees C. The resulting coating after annealing to 1140 degrees C is a mixture of t-ZrO2, m-ZrO2, and bcc-Cr. The air-annealed sample shows t-ZrO2 formation starting at similar to 750 degrees C. The resulting coating after annealing to 975 degrees C is a mixture of t-ZrO2 and alpha-Cr2O3 (with dissolved Zr). The microstructure coarsened slightly during annealing, but the mechanical properties are maintained, with no detectable bcc-Cr formation. A larger t-ZrO2 fraction compared with alpha-Cr2O3 is observed in the vacuum-annealed coating compared with the air-annealed coating at 975 degrees C. The results indicate that the studied pseudo-binary oxide is more stable in air atmosphere than in vacuum.</p>","","","","","","","","","","","","","2020-02-17","2020-02-17","2021-03-19","http://liu.diva-portal.org/smash/get/diva2:1393931/FULLTEXT01.pdf","","18","","1","urn:nbn:se:liu:diva-156603","","","","","true","","",""
"1384246","Edström, Daniel [daned22] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Orebro Univ, Sweden);Sangiovanni, Davide Giuseppe [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Ruhr Univ Bochum, Germany);Landälv, Ludvig [ludla97] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Sandvik Coromant AB, Sweden);Eklund, Per [perek02] [0000-0003-1785-0864] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Greene, Joseph E [josgr17] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Illinois, IL 61801 USA; Univ Illinois, IL 61801 USA; Natl Taiwan Univ Sci and Technol, Taiwan);Petrov, Ivan [ivape26] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Illinois, IL 61801 USA; Univ Illinois, IL 61801 USA);Hultman, Lars [larhu75] [0000-0002-2837-3656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Chirita, Valeriu [valch35] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Mechanical properties of VMoNO as a function of oxygen concentration: Toward development of hard and tough refractory oxynitrides","Artikel i tidskrift","Refereegranskat","eng","Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films","0734-2101","1520-8559","published","37","6","","","","2019","","","","A V S AMER INST PHYSICS","","","","","","","10.1116/1.5125302","000504231200029","","","urn:nbn:se:liu:diva-163046","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|Swedish Government Strategic Research Area Grant in Materials Science on Advanced Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; Olle Engkvist Foundation; competence center FunMat-II - Swedish Agency for Innovation Systems (Vinnova)Vinnova [2016-05156]</p>","<p>Improved toughness is a central goal in the development of wear-resistant refractory ceramic coatings. Extensive theoretical and experimental research has revealed that NaCl-structure VMoN alloys exhibit surprisingly high ductility combined with high hardness and toughness. However, during operation, protective coatings inevitably oxidize, a problem that may compromise material properties and performance. Here, the authors explore the role of oxidation in altering VMoN properties. Density functional theory and theoretical intrinsic hardness models are used to investigate the mechanical behavior of cubic V0.5Mo0.5N1-xOx solid solutions as a function of the oxygen concentration x. Elastic constant and intrinsic hardness calculations show that oxidation does not degrade the mechanical properties of V0.5Mo0.5N. Electronic structure analyses indicate that the presence of oxygen reduces the covalent bond character, which slightly lowers the alloy strength and intrinsic hardness. Nevertheless, the character of metallic d-d states, which are crucial for allowing plastic deformation and enhancing toughness, remains unaffected. Overall, the authors results suggest that VMoNO oxynitrides, with oxygen concentrations as high as 50%, possess high intrinsic hardness, while still being ductile. Published by the AVS.</p>","","","","","","","","","","","","","2020-01-09","2020-01-09","2021-03-19","http://liu.diva-portal.org/smash/get/diva2:1384246/FULLTEXT01.pdf","","8","","1","","","","","061508","false","","",""
"1384240","Landälv, Ludvig [ludla97] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Sandvik Coromant AB, Sweden);Gothelid, Emmanuelle (Sandvik Coromant AB, Sweden);Jensen, Jens [jenje80] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Greczynski, Grzegorz [grzgr49] [0000-0002-4898-5115] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Lu, Jun [junlu07] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ahlgren, Mats (Sandvik Coromant AB, Sweden);Hultman, Lars [larhu75] [0000-0002-2837-3656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Eklund, Per [perek02] [0000-0003-1785-0864] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Influence of Si doping and O-2 flow on arc-deposited (Al,Cr)(2)O-3 coatings","Artikel i tidskrift","Refereegranskat","eng","Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films","0734-2101","1520-8559","published","37","6","","","","2019","","","","A V S AMER INST PHYSICS","","","","","","","10.1116/1.5118312","000504231200037","","","urn:nbn:se:liu:diva-163048","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|Swedish Research Council (VR)Swedish Research Council [621-212-4368, 330-2014-6336, 2018-03957]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation [KAW2016.0358]; Marie Sklodowska Curie Actions, Cofund [INCA 600398]; Swedish Foundation for Strategic Research (SSF) through the Future Research Leaders 6 program; Swedish Research Council VR-RFISwedish Research Council [821-2012-5144, 2017-00646_9]; Swedish Foundation for Strategic Research (SSF)Swedish Foundation for Strategic Research [RIF14-0053]; VINNOVAVinnova [2018-04290]</p>","<p>(Al,Cr)(2)O-3 coatings with Al/( Al + Cr) = 0.5 or Al = 70 at. %, doped with 0, 5, or 10 at. % Si, were deposited on hard metal and Si(100) substrates to elucidate the influence of Si on the resulting coatings. The chemical analysis of the coatings showed between 3.3 and 7.4 at. % metal fraction Si incorporated into all studied coatings depending on cathode Si composition. The incorporated Si content does not change significantly with different oxygen flows covering a wide range of deposition conditions from low to high O-2 flow during growth. The addition of Si promotes the metastable B1-like cubic structure over the thermodynamically stable corundum structure. The hardness determined by nanoindentation of the as-deposited coatings is slightly reduced upon Si incorporation as well as upon increased Al content. Si is found enriched in droplets but can also be found at a lower content, evenly spread, without visible segregation at the similar to 5 nm scale, in the actual oxide coating. The positive effect of improved cathode erosion upon Si incorporation has to be balanced against the promotion of the metastable B1-like structure, having lower room temperature hardness and inferior thermal stability compared to the corundum structure. Published by the AVS.</p>","","","","","","","","","","","","","2020-01-09","2020-01-09","2021-03-19","http://liu.diva-portal.org/smash/get/diva2:1384240/FULLTEXT01.pdf","","9","","1","urn:nbn:se:liu:diva-156603","","","","061516","false","","",""
"1328791","Mukhamedov, B. O. (Natl Univ Sci and Technol MISIS, Russia);Saenko, I (Freiberg Univ Min and Technol, Germany; Russian Acad Sci, Russia);Ponomareva, A. V (Natl Univ Sci and Technol MISIS, Russia);Kriegel, M. J. (Freiberg Univ Min and Technol, Germany);Chugreev, A. (Leibniz Univ Hannover, Germany);Udovsky, A. (Russian Acad Sci, Russia; Natl Res Nucl Univ MEPhl, Russia);Fabrichnaya, O. (Freiberg Univ Min and Technol, Germany);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Thermodynamic and physical properties of Zr3Fe and ZrFe2 intermetallic compounds","Artikel i tidskrift","Refereegranskat","eng","Intermetallics (Barking)","0966-9795","1879-0216","published","109","","","189","196","2019","","","","ELSEVIER SCI LTD","","","","","","","10.1016/j.intermet.2019.01.018","000466821500025","","","urn:nbn:se:liu:diva-157517","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Ministry of Science and High Education of the Russian Federation [K2-2019-001, 211]; Strategic Research Areas the Swedish e-Science Research Centre (SeRC); Advanced Functional Materials at Linkoping University (Faculty Grant SFOMatLiU) [2009 00971]; German Research Foundation [SFB 799]; Russian Foundation for Basic Research [19-03-00530_a]</p>","<p>Experimental differential scanning calorimetry measurements and ab-initio simulations were carried out to define the heat capacities of Zr3Fe and C15-ZrFe2 compounds from 0 K up to their maximum stability temperatures. Experimental measurements of heat capacity of each compound were performed for the first time in wide range of temperatures. Density functional theory and quasi-harmonic approximation (QHA) were employed to calculate the free energy of the studied systems as a function of volume and temperature. A good agreement was observed between theoretical and experimental heat capacities within validity range of the QHA. This makes it possible to combine theoretical and experimental data to determine the standard entropies of intermetallic compounds.</p>","","","","","","","","","","","","","2019-06-23","2019-06-23","2021-04-03","http://liu.diva-portal.org/smash/get/diva2:1328791/FULLTEXT01.pdf","","8","","1","","","","","","false","","",""
"1183657","Mozafari, Elham [elhmo04] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Max Planck Inst Eisenforsch GmbH, Germany);Belov, Maxim P. (NUST MISIS, Russia);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Effect of the lattice dynamics on the electronic structure of paramagnetic NiO within the disordered local moment picture","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","97","3","","","","2018","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.97.035152","000423347500001","","","urn:nbn:se:liu:diva-145131","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Swedish Research Council (VR) [2015-04391, 621-2011-4417, 330-2014-6336]; Ministry of Education and Science of the Russian Federation [14.Y26.31.0005, K2-2017-080]; Marie Sklodowska Curie Actions [INCA 600398]; Swedish Foundation for Strategic Research (SSF) through the future research leaders 6 program; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFOMatLiU) [2009 00971]</p>","<p>Using the disordered local moments approach in combination with the ab initio molecular dynamics method, we simulate the behavior of a paramagnetic phase of NiO at finite temperatures to investigate the effect of magnetic disorder, thermal expansion, and lattice vibrations on its electronic structure. In addition, we study its lattice dynamics. We verify the reliability of our theoretical scheme via comparison of our results with available experiment and earlier theoretical studies carried out within static approximations. We present the phonon dispersion relations for the paramagnetic rock-salt (B1) phase of NiO and demonstrate that it is dynamically stable. We observe that including the magnetic disorder to simulate the paramagnetic phase has a small yet visible effect on the band gap. The amplitude of the local magnetic moment of Ni ions from our calculations for both antiferromagnetic and paramagnetic phases agree well with other theoretical and experimental values. We demonstrate that the increase of temperature up to 1000 K does not affect the electronic structure strongly. Taking into account the lattice vibrations and thermal expansion at higher temperatures have amajor impact on the electronic structure, reducing the band gap from similar to 3.5 eV at 600 K to similar to 2.5 eV at 2000 K. We conclude that static lattice approximations can be safely employed in simulations of the paramagnetic state of NiO up to relatively high temperatures (similar to 1000 K), but as we get closer to the melting temperature vibrational effects become quite large and therefore should be included in the calculations.</p>","","","","","","","","","","","","","2018-02-19","2018-02-19","2018-03-09","http://liu.diva-portal.org/smash/get/diva2:1183657/FULLTEXT01.pdf","","4","","2","","","","","035152","false","","",""
"1192456","Spektor, Kristina (ESRF, France);Crichton, Wilson A. (ESRF, France);Konar, Sumit (Univ Edinburgh, Scotland; Univ Edinburgh, Scotland);Filippov, Stanislav [stafi86] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Klarbring, Johan [johkl85] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Haussermann, Ulrich (Stockholm Univ, Sweden)","Unraveling Hidden Mg-Mn-H Phase Relations at High Pressures and Temperatures by in Situ Synchrotron Diffraction","Artikel i tidskrift","Refereegranskat","eng","Inorganic Chemistry","0020-1669","1520-510X","published","57","3","","1614","1622","2018","","","","AMER CHEMICAL SOC","","","","","","","10.1021/acs.inorgchem.7b02968","000424730800075","29323885","","urn:nbn:se:liu:diva-145773","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|Swedish Research Council (VR) [2013-4690, 2014-4750]; Swedish Government Strategic Research Area Grant in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; Carl Tryggers Stiftelse (CTS) for Vetenskaplig Forskning [16:198]</p>","<p>The MgMnH system was investigated by in situ high pressure studies of reaction mixtures MgH2MnH2. The formation conditions of two complex hydrides with composition Mg3MnH7 were established. Previously known hexagonal Mg3MnH7 (h-Mg3MnH7) formed at pressures 1.52 GPa and temperatures between 480 and 500 degrees C, whereas an orthorhombic form (o-Mg3MnH7) was obtained at pressures above 5 GPa and temperatures above 600 degrees C. The crystal structures of the polymorphs feature octahedral [Mn(I)H-6](5) complexes and interstitial H-. Interstitial H- is located in trigonal bipyramidal and square pyramidal interstices formed by Mg2+ ions in h- and o-Mg3MnH7, respectively. The hexagonal form can be retained at ambient pressure, whereas the orthorhombic form upon decompression undergoes a distortion to monoclinic Mg3MnH7 (m-Mg3MnH7). The structure elucidation of o- and m-Mg3MnH7 was aided by first-principles density functional theory (DFT) calculations. Calculated enthalpy versus pressure relations predict m- and o-Mg3MnH7 to be more stable than h-Mg3MnH7 above 4.3 GPa. Phonon calculations revealed o-Mg3MnH7 to be dynamically unstable at pressures below 5 GPa, which explains its phase transition to m-Mg3MnH7 on decompression. The electronic structure of the quenchable polymorphs h- and m-Mg3MnH7 is very similar. The stable 18-electron complex [MnH6](5-) is mirrored in the occupied states, and calculated band gaps are around 1.5 eV. The study underlines the significance of in situ investigations for mapping reaction conditions and understanding phase relations for hydrogen-rich complex transition metal hydrides.</p>","","","","","","","","","","","","","2018-03-22","2018-03-22","2018-03-22","","","7","","2","","","","","","false","","",""
"1199726","Tasnadi, Ferenc [ferta55] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia);Wang, Fei [feiwa67] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Saarland Univ, Germany);Odén, Magnus [magod41] [0000-0002-2286-5588] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Nanostrukturerade material [2221]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia)","Thermal expansion of quaternary nitride coatings","Artikel i tidskrift","Refereegranskat","eng","Journal of Physics: Condensed Matter","0953-8984","1361-648X","published","30","13","","","","2018","","","","IOP PUBLISHING LTD","","","","","","","10.1088/1361-648X/aab0b8","000426931800001","29460845","","urn:nbn:se:liu:diva-147079","","","thermal expansion; Ti-Al-N systems; quaternary alloys","Energiteknik (20304)","","","<p>Funding Agencies|Swedish Foundation for Strategic Research (SSF) program SRL Grant [10-0026, 621-2012-4401]; Vinnova [2016-05156]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; Vinnova (M-ERA.NET project: Multi-scale computational-driven design of novel hard nanostructured Coatings-MC2); Ministry of Education and Science of the Russian Federation [14.Y26.31.0005, K2-2017-080]; Erasmus Mundus Joint European Doctoral Programme DocMASE</p>","<p>The thermal expansion coefficient of technologically relevant multicomponent cubic nitride alloys are predicted using the Debye model with ab initio elastic constants calculated at 0 K and an isotropic approximation for the Gruneisen parameter. Our method is benchmarked against measured thermal expansion of TiN and Ti(1-x)AlxN as well as against results of molecular dynamics simulations. We show that the thermal expansion coefficients of Ti(1-x-y)XyAlxN (X = Zr, Hf, Nb, V, Ta) solid solutions monotonously increase with the amount of alloying element X at all temperatures except for Zr and Hf, for which they instead decrease for y greater than or similar to 0.5.</p>","","","","","","","","","","","","","2018-04-22","2018-04-22","2018-04-22","","","4","","1","","","","","135901","false","","",""
"1206665","Lischka, Matthias (Tech Univ Munich, Germany; Deutsch Museum, Germany);Fritton, Massimo (Tech Univ Munich, Germany; Deutsch Museum, Germany);Eichhorn, Johanna (Tech Univ Munich, Germany; Deutsch Museum, Germany);Vyas, Vijay S. (Max Planck Inst Solid State Res, Germany; Marquette Univ, WI 53233 USA);Strunskus, Thomas (Christian Albrechts Univ Kiel, Germany);Lotsch, Bettina V. (Max Planck Inst Solid State Res, Germany; Nanosyst Initiat Munich, Germany; Ctr NanoSci, Germany; Univ Munich LMU, Germany);Björk, Jonas [jonbj66] [0000-0002-1345-0006] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Heckl, Wolfgang M. (Tech Univ Munich, Germany; Deutsch Museum, Germany; Nanosyst Initiat Munich, Germany; Ctr NanoSci, Germany);Lackinger, Markus (Tech Univ Munich, Germany; Deutsch Museum, Germany; Nanosyst Initiat Munich, Germany; Ctr NanoSci, Germany)","On-Surface Polymerization of 1,6-Dibromo-3,8-diiodpyrene-A Comparative Study on Au(111) Versus Ag(111) by STM, XPS, and NEXAFS","Artikel i tidskrift","Refereegranskat","eng","The Journal of Physical Chemistry C","1932-7447","1932-7455","published","122","11","","5967","5977","2018","","","","AMER CHEMICAL SOC","","","","","","","10.1021/acs.jpcc.7b10403","000428356700016","","","urn:nbn:se:liu:diva-147413","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|The excellence cluster Nanosystems Initiative Munich; Max Planck Society</p>","<p>The surface chemistry of 1,6-dibromo-3,8-diiodopyrene (Br2I2Py) is comparatively studied on Au(111) versus Ag(111) surfaces under ultrahigh vacuum conditions by a combination of high-resolution scanning tunneling microscopy (STM) and X-ray spectroscopy. The chemical state of the molecular networks, that is, the dehalogenation and the possible formation of organometallic intermediates, is assessed by X-ray photoelectron spectroscopy. In addition, pyrene tilt angles are quantified by carbon K-edge near edge X-ray absorption fine structure experiments. Upon room-temperature (RT) deposition of Br2I2Py onto Au(111), only partial deiodination was found, and STM revealed the coexistence of ordered arrangements of both intact Br2I2Py molecules and organometallic dimers as well as few larger aggregates. Further annealing to 100 C triggered full deiodination followed by the formation of organometallic chains of otherwise still brominated molecules. By contrast, on Ag(111), iodine is fully and bromine is partly dissociated upon RT deposition of Br2I2Py. The initially disordered organometallic aggregates can be reorganized into more ordered structures by mild annealing at 125 degrees C. Yet, the conversion of the organometallic intermediates into well-defined cross-linked quasi 2D covalent networks was neither possible on Au(111) nor on Ag(111). This is attributed to the large steric hindrance in the covalently linked adsorbed state.</p>","","","","","","","","","","","","","2018-05-17","2018-05-17","2018-05-17","","","9","","1","","","","","","false","","",""
"1206485","Keller, Lukas (Goethe Univ, Germany);Al Mamoori, Mohanad K. I. (Goethe Univ, Germany);Pieper, Jonathan (Goethe Univ, Germany);Gspan, Christian (Graz Ctr Electron Microscopy, Austria);Stockem, Irina [irist97] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Schroeder, Christian (Bielefeld Univ Appl Sci, Germany);Barth, Sven (Vienna Univ Technol, Austria);Winkler, Robert (Graz Centre for Electron Microscopy, Graz, Austria);Plank, Harald (Graz Univ Technol, Austria);Pohlit, Merlin (Goethe Univ, Germany);Mueller, Jens (Goethe Univ, Germany);Huth, Michael (Goethe Univ, Germany)","Direct-write of free-form building blocks for artificial magnetic 3D lattices","Artikel i tidskrift","Refereegranskat","eng","Scientific Reports","2045-2322","2045-2322","published","8","","","","","2018","","","","NATURE PUBLISHING GROUP","","","","","","","10.1038/s41598-018-24431-x","000430280600012","29670129","","urn:nbn:se:liu:diva-147798","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Deutsche Forschungsgemeinschaft (DFG) [SFB/TR 49]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; Faculty of Materials Engineering, University of Babylon, Babylon, Iraq; Deutscher Akademischer Austauschdienst (DAAD); COST Action [CM1301]</p>","<p>By the fabrication of periodically arranged nanomagnetic systems it is possible to engineer novel physical properties by realizing artificial lattice geometries that are not accessible via natural crystallization or chemical synthesis. This has been accomplished with great success in two dimensions in the fields of artificial spin ice and magnetic logic devices, to name just two. Although first proposals have been made to advance into three dimensions (3D), established nanofabrication pathways based on electron beam lithography have not been adapted to obtain free-form 3D nanostructures. Here we demonstrate the direct-write fabrication of freestanding ferromagnetic 3D nano-architectures. By employing micro-Hall sensing, we have determined the magnetic stray field generated by our free-form structures in an externally applied magnetic field and we have performed micromagnetic and macro-spin simulations to deduce the spatial magnetization profiles in the structures and analyze their switching behavior. Furthermore we show that the magnetic 3D elements can be combined with other 3D elements of different chemical composition and intrinsic material properties.</p>","","","","","","","","","","","","","2018-05-17","2018-05-17","2018-06-04","http://liu.diva-portal.org/smash/get/diva2:1206485/FULLTEXT01.pdf","","12","","1","","","","","6160","false","","",""
"1213614","Tasnadi, Ferenc [ferta55] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia);Rogström, Lina [linro82] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Nanostrukturerade material [2221]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Zhu, Jianqiang [jiazh32] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Wang, Fei [feiwa67] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Hsu, Tun-Wei [tunhs26] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Nanostrukturerade material [2221]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Lind, Hans [hanli61] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia);Johansson, Mats [matjo02] [0000-0003-4577-0976] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Nanostrukturerade material [2221]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (SECO Tools AB, Sweden);Odén, Magnus [magod41] [0000-0002-2286-5588] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Nanostrukturerade material [2221]) (Linköpings universitet [276], Tekniska fakulteten [872902])","High temperature thermodynamics of spinodal decomposition in arc deposited TixNbyAlzN coatings","Artikel i tidskrift","Refereegranskat","eng","Materials & design","0264-1275","1873-4197","published","150","","","165","170","2018","","","","Elsevier","","","","","","","10.1016/j.matdes.2018.04.033","000432565300019","","2-s2.0-85045795846","urn:nbn:se:liu:diva-148238","","","Hard coating films; NbN; Cathodic arc deposition; Thermodynamic stability; Hardness","Metallurgi och metalliska material (20506)","","","<p>Funding Agencies|VINN Excellence Center Functional Nanoscale Materials (FunMat-II) [201605156]; Swedish Research Council (VR) [201504391]; Swedish Foundation for Strategic Research (SSF) program [621-2012-4401]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; Vinnova [201302355]; Ministry of Education and Science of the Russian Federation [14.Y26.31.0005, K2-2017-080, 211]</p>","<p data-select-like-a-boss=""1"">Using first principles calculations and experimental methods we show that B1 structured solid solution TixNbyAlzN can be grown. The mixing free energy surface indicates that the alloys should decompose. Theoretical analysis of the thermodynamic driving force towards the spinodal decomposition shows that the force can be different in alloys with equally low thermodynamic stability but different Nb content, indicating that the detailed picture of the decomposition should also be different. Electron microscopy and nanoindentation underlines different age hardening of the samples. We demonstrate that an alloy with the optimized composition, Ti0.42Nb0.17Al0.41N combines high thermal stability and age hardening behavior.</p>","","","","","","","","","","","","","2018-06-05","2018-06-05","2018-06-12","","","9","","1","","","","","","true","","",""
"1218959","Li, Qing (Soochow Univ, Peoples R China);Yang, Biao (Soochow Univ, Peoples R China);Björk, Jonas [jonbj66] [0000-0002-1345-0006] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Zhong, Qigang (Soochow Univ, Peoples R China; Justus Liebig Univ Giessen, Germany);Ju, Huanxin (Univ Sci and Technol China, Peoples R China);Zhang, Junjie (Soochow Univ, Peoples R China);Cao, Nan (Soochow Univ, Peoples R China);Shi, Ziliang (Soochow Univ, Peoples R China);Zhang, Haiming (Soochow Univ, Peoples R China);Ebeling, Daniel (Justus Liebig Univ Giessen, Germany);Schirmeisen, Andre (Justus Liebig Univ Giessen, Germany);Zhu, Junfa (Univ Sci and Technol China, Peoples R China);Chi, Lifeng (Soochow Univ, Peoples R China)","Hierarchical Dehydrogenation Reactions on a Copper Surface","Artikel i tidskrift","Refereegranskat","eng","Journal of the American Chemical Society","0002-7863","1520-5126","published","140","19","","6076","6082","2018","","","","AMER CHEMICAL SOC","","","","","","","10.1021/jacs.7b12278","000432753400009","29543446","","urn:nbn:se:liu:diva-148386","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|National Science Foundation of China [21661132006, 21790053, 21622306, 91545127, 21473178, 21773222]; National Major State Basic Research Development Program of China [2017YFA0205002, 2014CB932600]; Natural Science Foundation of Jiangsu Province [BK20140305, BK20130285]</p>","<p>Hierarchical control of chemical reactions is being considered as one of the most ambitious and challenging topics in modern organic chemistry. In this study, we have realized the one-by-one scission of the X-H bonds (X = N and C) of aromatic amines in a controlled fashion on the Cu(lll) surface. Each dehydrogenation reaction leads to certain metal-organic supramolecular structures, which were monitored in single-bond resolution via scanning tunneling microscopy and noncontact atomic force microscopy. Moreover, the reaction pathways were elucidated from X-ray photoelectron spectroscopy measurements and density functional theory calculations. Our insights pave the way for connecting molecules into complex structures in a more reliable and predictable manner, utilizing carefully tuned stepwise on-surface synthesis protocols.</p>","","","","","","","","","","","","","2018-06-15","2018-06-15","2018-06-15","","","13","","2","","","","","","false","","",""
"1205882","Silverå Ejneby, Malin [malsi14] (Linköpings universitet [276], Institutionen för klinisk och experimentell medicin [322], Avdelning för neurobiologi [877701]) (Linköpings universitet [276], Medicinska fakulteten [872900]);Wu, Xiongyu [xiowu62] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Kemi [9600]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ottosson, Nina [ninot92] (Linköpings universitet [276], Institutionen för klinisk och experimentell medicin [322], Avdelning för neurobiologi [877701]) (Linköpings universitet [276], Medicinska fakulteten [872900]);Münger, E Peter [petmu26] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Lundström, Ingemar [inglu57] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Sensor- och aktuatorsystem [878650]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Konradsson, Peter [petko14] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Kemi [9600]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Elinder, Fredrik [freel71] [0000-0001-9125-5583] (Linköpings universitet [276], Institutionen för klinisk och experimentell medicin [322], Avdelning för neurobiologi [877701]) (Linköpings universitet [276], Medicinska fakulteten [872900])","Atom-by-atom tuning of the electrostatic potassium-channel modulator dehydroabietic acid","Artikel i tidskrift","Refereegranskat","eng","The Journal of General Physiology","0022-1295","1540-7748","published","150","5","","731","750","2018","","","New York, United States","Rockefeller Institute for Medical Research","","","","","","","10.1085/jgp.201711965","000434417800008","","2-s2.0-85046705149","urn:nbn:se:liu:diva-147837","","","","Fysiologi (30106)","","","<p>Funding agencies: Swedish Research Council [2016-02615]; Swedish Heart-Lung Foundation [20150672]; Swedish Brain Foundation [2016-0326]</p>","<p data-select-like-a-boss=""1"">Dehydroabietic acid (DHAA) is a naturally occurring component of pine resin that was recently shown to open voltage-gated potassium (KV) channels. The hydrophobic part of DHAA anchors the compound near the channel’s positively charged voltage sensor in a pocket between the channel and the lipid membrane. The negatively charged carboxyl group exerts an electrostatic effect on the channel’s voltage sensor, leading to the channel opening. In this study, we show that the channel-opening effect increases as the length of the carboxyl-group stalk is extended until a critical length of three atoms is reached. Longer stalks render the compounds noneffective. This critical distance is consistent with a simple electrostatic model in which the charge location depends on the stalk length. By combining an effective anchor with the optimal stalk length, we create a compound that opens the human KV7.2/7.3 (M type) potassium channel at a concentration of 1 µM. These results suggest that a stalk between the anchor and the effector group is a powerful way of increasing the potency of a channel-opening drug.</p>","","","","","","","","","","","","","2018-05-15","2018-05-15","2018-06-28","http://liu.diva-portal.org/smash/get/diva2:1205882/FULLTEXT01.pdf","","7","","2","urn:nbn:se:liu:diva-147838","","","","","true","","",""
"1236445","Garhammer, Julian (Univ Bayreuth, Germany);Hofmann, Fabian (Univ Bayreuth, Germany);Armiento, Rickard [ricar47] [0000-0002-5571-0814] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Kuemmel, Stephan (Univ Bayreuth, Germany)","On the challenge to improve the density response with unusual gradient approximations","Artikel i tidskrift","Refereegranskat","eng","European Physical Journal B: Condensed Matter Physics","1434-6028","1434-6036","published","91","7","","","","2018","","","","SPRINGER","","","","","","","10.1140/epjb/e2018-90119-4","000437971200005","","","urn:nbn:se:liu:diva-149853","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Deutsche Forschungsgemeinschaft [Graduiertenkolleg 1640]; study program ""Biological Physics"" of the Elite Network of Bavaria; German-Israeli Foundation for Scientific Research and Development; University of Bayreuth Graduate School; Swedish Research Council (VR) project [2016-04810]; Swedish e-Science Research Centre (SeRC)</p>","<p>Certain excitations, especially ones of long-range charge transfer character, are poorly described by time-dependent density functional theory (TDDFT) when typical (semi-)local functionals are used. A proper description of these excitations would require an exchange-correlation response differing substantially from the usual (semi-) local one. It has recently been shown that functionals of the generalized gradient approximation (GGA) type can yield unusual potentials, mimicking features of the exact exchange derivative discontinuity and showing divergences on orbital nodal surfaces. We here investigate whether these unusual potential properties translate into beneficial response properties. Using the Sternheimer formalism we closely investigate the response obtained with the 2013 exchange approximation by Armiento and Kummel (AK13) and the 1988 exchange approximation by Becke (B88), both of which show divergences on orbital nodal planes. Numerical calculations for Na-2 as well as analytical and numerical calculations for the hydrogen atom show that the response of AK13 behaves qualitatively different from usual semi-local functionals. However, the AK13 functional leads to fundamental instabilities in the asymptotic region that prevent its practical application in TDDFT. Our findings may help the development of future improved functionals. They also corroborate that the frequency-dependent Sternheimer formalism is excellently suited for running and analyzing TDDFT calculations.</p>","","","","","","","","","","","","","2018-08-02","2018-08-02","2018-08-02","","","4","","1","","","","","159","false","","",""
"1229737","Ponomareva, A. V. (Natl Univ Sci and Technol MISIS, Russia);Ruban, A. V. (KTH Royal Inst Technol, Sweden; Leoben Forsch GmbH, Austria);Mukhamedov, B. O. (Natl Univ Sci and Technol MISIS, Russia);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Effect of multicomponent alloying with Ni, Mn and Mo on phase stability of bcc Fe-Cr alloys","Artikel i tidskrift","Refereegranskat","eng","Acta Materialia","1359-6454","1873-2453","published","150","","","117","129","2018","","","","PERGAMON-ELSEVIER SCIENCE LTD","","","","","","","10.1016/j.actamat.2018.02.007","000433272400011","","","urn:nbn:se:liu:diva-149377","","","First-principles calculations; Fe-Cr system; Multicomponent alloying; Phase stability; Spinodal decompositon; Mixing enthalpy","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Swedish Research Council [2015-04391]; Swedish Government Strategic Research Areas in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; Swedish e-science Research Centre (SeRC); Ministry of Education and Science of the Russian Federation [14.Y26.31.0005]; Ministry of Education and Science of the Russian Federation in the framework of Increase Competitiveness Program of NUST ""MISIS"" [K2-2017-080]; Swedish Research Council (VR project) [2015-05538]; European Research Council; VINNEX center Hero-m - Swedish Governmental; Agency for Innovation Systems (VINNOVA); Swedish industry; Royal Institute of Technology (KTH); Austrian Federal Government (Bundesministerium fur Verkehr, Innovation und Technologie); Austrian Federal Government (Bundesministerium fur Wirtschaft, Familie und Jugend)</p>","<p>Fe-Cr system attracts lot of attention in condensed matter physics due to its technological importance and extraordinary physics related to a non-trivial interplay between magnetic and chemical interactions. However, the effect of multicomponent alloying on the properties of Fe-Cr alloys are less studied. We have calculated the mixing enthalpy, magnetic moments, effective chemical, strain-induced and magnetic exchange interactions to investigate the alloying effect of Ni, Mn, Mo on the phase stability of the ferromagnetic bcc Fe Cr system at zero K. We demonstrate that the alloying reduces the stability of Fe-Cr alloys and expands the region of spinodal decomposition. At the same time, the mixing enthalpy in ternary Fe100-c-05CrcNi05 alloys indicates a stability of solid solution phase up to 6 at. % Cr. In Fem(100-c-07)CrNi(05)Mn(01)Mo(01) alloys, we did not find any alloy composition that has negative enthalpy of formation. Analyzing magnetic and electronic properties of the alloys and investigating magnetic, chemical and strain-induced interactions in the studied systems, we provide physically transparent picture of the main factors leading to the destabilization of the Fe-Cr solid solutions by the multicomponent alloying with Ni, Mn, Mo. (C) 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.</p>","","","","","","","","","","","","","2018-07-02","2018-07-02","2018-08-03","","","4","","2","","","","","","false","","",""
"1234387","Burakovsky, Leonid (Los Alamos Natl Lab, NM 87545 USA);Burakovsky, Naftali (Los Alamos Natl Lab, NM 87545 USA);Preston, Dean (Los Alamos Natl Lab, NM 87545 USA);Simak, Sergei I [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Systematics of the Third Row Transition Metal Melting: The HCP Metals Rhenium and Osmium","Artikel i tidskrift","Refereegranskat","eng","Crystals","2073-4352","","published","8","6","","","","2018","","","","MDPI","","","","","","","10.3390/cryst8060243","000436129400012","","","urn:nbn:se:liu:diva-149722","","","quantum molecular dynamics; phase diagram; melting curve; transition metal","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|US DOE/NNSA</p>","<p>The melting curves of rhenium and osmium to megabar pressures are obtained from an extensive suite of ab initio quantum molecular dynamics (QMD) simulations using the Z method. In addition, for Re, we combine QMD simulations with total free energy calculations to obtain its phase diagram. Our results indicate that Re, which generally assumes a hexagonal close-packed (hcp) structure, melts from a face-centered cubic (fcc) structure in the pressure range 20-240 GPa. We conclude that the recent DAC data on Re to 50 GPa in fact encompass both the true melting curve and the low-slope hcp-fcc phase boundary above a triple point at (20 GPa, 4240 K). A linear fit to the Re diamond anvil cell (DAC) data then results in a slope that is 2.3 times smaller than that of the actual melting curve. The phase diagram of Re is topologically equivalent to that of Pt calculated by us earlier on. Regularities in the melting curves of Re, Os, and five other 3rd-row transition metals (Ta, W, Ir, Pt, Au) form the 3rd-row transition metal melting systematics. We demonstrate how this systematics can be used to estimate the currently unknown melting curve of the eighth 3rd-row transition metal Hf.</p>","","","","","","","","","","","","","2018-07-24","2018-07-24","2018-08-14","http://liu.diva-portal.org/smash/get/diva2:1234387/FULLTEXT01.pdf","","4","","0","","","","","243","false","true","",""
"1235312","Ektarawong, Annop [annek02] [0000-0002-6059-6833] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Max Planck Inst Eisenforsch GmbH, Germany)","Stability of SnSe<sub>1-x</sub>S<sub>x</sub> solid solutions revealed by first-principles cluster expansion","Artikel i tidskrift","Refereegranskat","eng","Journal of Physics: Condensed Matter","0953-8984","1361-648X","published","30","29","","","","2018","","","","IOP PUBLISHING LTD","","","","","","","10.1088/1361-648X/aacb9c","000436395200001","29889052","","urn:nbn:se:liu:diva-149681","","","configurational thermodynamics; first-principles approach; cluster-expansion formalism; SnSe1-xSx alloy","Fysikalisk kemi (10402)","","","<p>Funding Agencies|Swedish Research Council (VR) [2014-6336]; Marie Sklodowska Curie Actions, Cofund [INCA 600398]; Swedish Foundation for Strategic Research (SSF); Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]</p>","<p>The configurational thermodynamics of a pseudo-binary alloy SnSe1-xSx in the Pnma phase is studied using first-principles cluster-expansion method in combination with canonical Monte Carlo simulations. We find that, despite the alloy having a tendency toward a phase decomposition into SnSe and SnS at 0 K, the two constituent binaries readily mix with each other to form random SnSe1-xSx solid solutions even at a temperature below room temperature. The obtained isostructural phase diagram of SnSe1-xSx reveals that the alloy is thermodynamically stable as a single-phase random solid solution over a whole composition range above 200 K. These findings provide a fundamental understanding on the alloying behavior of SnSe1-xSx and bring clarity to the debated clustering tendency in this alloy system.</p>","","","","","","","","","","","","","2018-07-25","2018-07-25","2018-08-14","http://liu.diva-portal.org/smash/get/diva2:1235312/FULLTEXT01.pdf","","2","","1","","","","","29LT01","false","true","",""
"1234393","Sagun, V. V. (Natl Acad Sci Ukraine, Ukraine; Univ Lisbon, Portugal);Bugaev, K. A. (Natl Acad Sci Ukraine, Ukraine);Ivanytskyi, A. I. (Natl Acad Sci Ukraine, Ukraine);Yakymenko, Ivan (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Nikonov, E. G. (JINR, Russia);Taranenko, A. V. (Natl Res Nucl Univ MEPhI Moscow Engn Phys Inst, Russia);Greiner, C. (Goethe Univ, Germany);Blaschke, D. B. (Natl Res Nucl Univ MEPhI Moscow Engn Phys Inst, Russia; Univ Wroclaw, Poland; JINR Dubna, Russia);Zinovjev, G. M. (Natl Acad Sci Ukraine, Ukraine)","Hadron resonance gas model with induced surface tension","Artikel i tidskrift","Refereegranskat","eng","European Physical Journal A","1434-6001","1434-601X","published","54","6","","","","2018","","","","SPRINGER","","","","","","","10.1140/epja/i2018-12535-1","000436363800001","","","urn:nbn:se:liu:diva-149716","","","","Astronomi, astrofysik och kosmologi (10305)","","","<p>Funding Agencies|Section of Nuclear Physics of National Academy of Sciences of Ukraine; Fundacao pars a Ciencia e Tecnologia (FCT), Portugal; instituto Superior Tocnico, Universidade de Lisboa [UID/FIS/00099/2013]; Ministry of Science and Education of the Russian Federation [3.3380.2017/4.6]; National Research Nuclear University ""MEPhl"" in the framework of the Russian Academic Excellence Project [02.a03.21.0005]; HIC; MENAI Academic Excellence program [02.a03.21.0005]</p>","<p>Here we present a generalization of the multicomponent Van der Waals equation of state in the grand canonical ensemble. For the one-component case the third and fourth virial coefficients are calculated analytically. It is shown that the adjustment of a single model parameter allows us to reproduce the third and fourth virial coefficients of the gas of hard spheres with small deviations from their exact values. A thorough comparison of the compressibility factor and speed of sound of this model with the one- and two-component Carnahan-Starling equation of state is made. We show that the model with the induced surface tension can reproduce the results of the Carnahan-Starling equation of state up to the packing fractions 0.2-0.22 at which the Van der Waals equation of state is inapplicable. Using this approach we develop an entirely new hadron resonance gas model and apply it to a description of the hadron yield ratios measured at AGS, SPS, RHIC and ALICE energies of nuclear collisions. We confirm that the strangeness enhancement factor has a peak at low AGS energies and that there is a jump of chemical freeze-out temperature between the two highest AGS energies. Also we argue that the chemical equilibrium of strangeness, i.e gamma(s) similar or equal to 1, observed above the center of mass collision energy 8.7 GeV, may be related to a hadronization of quark gluon bags which have a Hagedorn mass spectrum, and, hence, it may be a new signal for the onset of deconfinement.</p>","","","","","","","","","","","","","2018-07-24","2018-07-24","2018-08-14","","","9","","1","","","","","100","false","","",""
"1218607","Ektarawong, Annop [annek02] [0000-0002-6059-6833] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Thermodynamic consideration and ground-state search of icosahedral boron subselenide B-12(B1-xSex)(2) from a first-principles cluster expansion","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","97","17","","","","2018","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.97.174103","000432960900001","","","urn:nbn:se:liu:diva-148388","","","","Annan fysik (10399)","","","<p>Funding Agencies|Swedish Foundation for Strategic Research (SSF) through the Future Research Leaders programme (the sixth generation)</p>","<p>The phase stability of icosahedral boron subselenide B-12(B1-xSex)(2), where 0.5 amp;lt;= x amp;lt;= 1, is explored using a first-principles cluster expansion. The results shows that, instead of a continuous solid solution, B-12(B1-xSex)(2) is thermodynamically stable as an individual line compound at the composition of B9.5Se. The ground-state configuration of B9.5Se is represented by a mixture of B-12(Se-Se), B-12(B-Se), and B-12(Se-B) with a ratio of 1: 1: 1, where they form a periodic ABCABC... stacking sequence of B-12(Se-Se), B-12(B-Se), and B-12(Se-B) layers along the c axis of the hexagonal conventional unit cell. The structural and electronic properties of the ground-state B9.5Se are also derived and discussed. By comparing the derived ground-state properties of B9.5Se to the existing experimental data of boron subselenide B similar to 13Se, I proposed that the as-synthesized boron subselenide B similar to 13Se, as reported in the literature, has the actual composition of B9.5Se.</p>","","","","","","","","","","","","","2018-06-14","2018-06-14","2018-08-29","","","1","","2","","","","","174103","false","","",""
"1218964","Ektarawong, Annop [annek02] [0000-0002-6059-6833] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Max Planck Inst Eisenforsch GmbH, Germany)","Structural models of increasing complexity for icosahedral boron carbide with compositions throughout the single-phase region from first principles","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","97","17","","","","2018","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.97.174104","000433010000001","","","urn:nbn:se:liu:diva-148384","","","","Annan fysik (10399)","","","<p>Funding Agencies|Swedish Research Council (VR) [2014-6336, 2014-4750]; Marie Sklodowska Curie Actions [INCA 600398]; Swedish Foundation for Strategic Research (SSF) through the Future Research Leaders 6 program; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]</p>","<p>We perform first-principles calculations to investigate the phase stability of boron carbide, concentrating on the recently proposed alternative structural models composed not only of the regularly studied B11Cp(CBC) and B-12(CBC), but also of B-12(CBCB) and B-12(B-4). We find that a combination of the four structural motifs can result in low-energy electron precise configurations of boron carbide. Among several considered configurations within the composition range of B10.5C and B4C, we identify in addition to the regularly studied B11Cp(CBC) at the composition of B4C two low-energy configurations, resulting in a new view of the B-C convex hull. Those are [B-12(CBC)](0.67)[B-12(B-4)](0.33) and [B-12(CBC)](0.67)[B-12(CBCB)](0.33), corresponding to compositions of B10.5C and B6.67C, respectively. As a consequence, B-12(CBC) at the composition of B6.5C, previously suggested in the literature as a stable configuration of boron carbide, is no longer part of the B-C convex hull. By inspecting the electronic density of states as well as the elastic moduli, we find that the alternative models of boron carbide can provide a reasonably good description for electronic and elastic properties of the material in comparison with the experiments, highlighting the importance of considering B-12(CBCB) and B-12(B-4), together with the previously proposed B11Cp(CBC) and B-12(CBC), as the crucial ingredients for modeling boron carbide with compositions throughout the single-phase region.</p>","","","","","","","","","","","","","2018-06-15","2018-06-15","2018-08-29","","","3","","2","","","","","174104","false","","",""
"1239747","Bykov, M. (Univ Bayreuth, Germany);Bykova, E. (Univ Bayreuth, Germany; DESY, Germany);Aprilis, G. (Univ Bayreuth, Germany);Glazyrin, K. (DESY, Germany);Koemets, E. (Univ Bayreuth, Germany);Chuvashova, I (Univ Bayreuth, Germany; Univ Bayreuth, Germany);Kupenko, I (Univ Munster, Germany);McCammon, C. (Univ Bayreuth, Germany);Mezouar, M. (European Synchrotron Radiat Facil, France);Prakapenka, V (Univ Chicago, IL 60437 USA);Liermann, H-P (DESY, Germany);Tasnadi, Ferenc [ferta55] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia);Ponomareva, A. V (Natl Univ Sci and Technol MISIS, Russia);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Dubrovinskaia, N. (Univ Bayreuth, Germany);Dubrovinsky, L. (Univ Bayreuth, Germany)","Fe-N system at high pressure reveals a compound featuring polymeric nitrogen chains","Artikel i tidskrift","Refereegranskat","eng","Nature Communications","2041-1723","2041-1723","published","9","","","","","2018","","","","NATURE PUBLISHING GROUP","","","","","","","10.1038/s41467-018-05143-2","000438684200008","30013071","","urn:nbn:se:liu:diva-150266","","","","Materialkemi (10403)","","","<p>Funding Agencies|National Science Foundation-Earth Sciences [EAR-1634415]; Department of Energy-GeoSciences [DE-FG02-94ER14466]; DOE Office of Science [DE-AC02-06CH11357]; Deutsche Forschungsgemeinschaft (DFG) [DU 954-11/1, DU 393-10/1]; Federal Ministry of Education and Research, Germany (BMBF) [5K16WC1]; Swedish Research Council [2015-04391]; VINN Excellence Center Functional Nanoscale Materials (FunMat-2) [2016-05156]; Swedish Government Strategic Research Areas in Materials Science on Functional Materials at Linkoping University [2009-00971]; Swedish e-Science Research Centre (SeRC); Ministry of Education and Science of the Russian Federation [14.Y26.31.0005, K2-2017-080]; RFBR [16-02-00797]</p>","<p>Poly-nitrogen compounds have been considered as potential high energy density materials for a long time due to the large number of energetic N-N or N=N bonds. In most cases high nitrogen content and stability at ambient conditions are mutually exclusive, thereby making the synthesis of such materials challenging. One way to stabilize such compounds is the application of high pressure. Here, through a direct reaction between Fe and N-2 in a laser-heated diamond anvil cell, we synthesize three ironnitrogen compounds Fe3N2, FeN2 and FeN4. Their crystal structures are revealed by single-crystal synchrotron X-ray diffraction. Fe3N2, synthesized at 50 GPa, is isostructural to chromium carbide Cr3C2. FeN2 has a marcasite structure type and features covalently bonded dinitrogen units in its crystal structure. FeN4, synthesized at 106 GPa, features polymeric nitrogen chains of [N-4(2-)](n) units. Based on results of structural studies and theoretical analysis, [N-4(2-)](n) units in this compound reveal catena-poly[tetraz-1-ene-1,4-diyl] anions.</p>","","","","","","","","","","","","","2018-08-17","2018-08-17","2018-09-10","http://liu.diva-portal.org/smash/get/diva2:1239747/FULLTEXT01.pdf","","16","","2","","","","","2756","false","true","",""
"1248626","Fritton, Massimo (Deutsch Museum, Germany; Tech Univ Munich, Germany);Otte, Katrin (Bavarian Acad Sci and Humanities, Germany);Björk, Jonas [jonbj66] [0000-0002-1345-0006] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Biswas, Pronay Kumar (Univ Siegen, Germany);Heckl, Wolfgang M. (Deutsch Museum, Germany; Tech Univ Munich, Germany);Schmittel, Michael (Univ Siegen, Germany);Lackinger, Markus (Deutsch Museum, Germany; Tech Univ Munich, Germany)","The influence of ortho-methyl substitution in organometallic self-assembly - a comparative study on Cu(111) vs. Ag(111)","Artikel i tidskrift","Refereegranskat","eng","Chemical Communications","1359-7345","1364-548X","published","54","70","","9745","9748","2018","","","","ROYAL SOC CHEMISTRY","","","","","","","10.1039/c8cc04854a","000442872000007","30109325","","urn:nbn:se:liu:diva-151185","","","","Oorganisk kemi (10404)","","","","<p>Metal surface-induced dehalogenation of precursors is known to initiate self-assembly of organometallic networks, where tectons are connected via carbon-metal-carbon (C-M-C) bonds. Even though reversibility of the C-M-C bonds facilitates structural equilibration, defects associated with highly bent organometallic linkages are still commonly observed. By introducing a steric hindrance to reduce the C-M-C bond angle flexibility, we find well ordered organometallic networks of an ortho-methyl substituted 1,3,5-tris(p-bromophenyl)-benzene analogue on Cu(111) after room-temperature (RT) deposition and on Ag(111) after annealing.</p>","","","","","","","","","","","","","2018-09-17","2018-09-17","2018-09-17","","","7","","1","","","","","","false","","",""
"1250605","Cai, Liangliang (Tongji Univ, Peoples R China);Yu, Xin (Tongji Univ, Peoples R China);Liu, Mengxi (Natl Ctr Nanosci and Technol, Peoples R China);Sun, Qiang (Tongji Univ, Peoples R China);Bao, Meiling (Tongji Univ, Peoples R China);Zha, Zeqi (Natl Ctr Nanosci and Technol, Peoples R China; Univ Chinese Acad Sci, Peoples R China);Pan, Jinliang (Natl Ctr Nanosci and Technol, Peoples R China; Univ Chinese Acad Sci, Peoples R China);Ma, Honghong (Tongji Univ, Peoples R China);Ju, Huanxin (Univ Sci and Technol China, Peoples R China);Hu, Shanwei (Univ Sci and Technol China, Peoples R China);Xu, Liang (Tongji Univ, Peoples R China);Zou, Jiacheng (Tongji Univ, Peoples R China);Yuan, Chunxue (Tongji Univ, Peoples R China);Jacob, Timo (Ulm Univ, Germany);Björk, Jonas [jonbj66] [0000-0002-1345-0006] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Zhu, Junfa (Univ Sci and Technol China, Peoples R China);Qu, Xiaohui (Natl Ctr Nanosci and Technol, Peoples R China; Univ Chinese Acad Sci, Peoples R China);Xu, Wei (Tongji Univ, Peoples R China)","Direct Formation of C-C Double-Bonded Structural Motifs by On-Surface Dehalogenative Homocoupling of gem-Dibromomethyl Molecules","Artikel i tidskrift","Refereegranskat","eng","ACS Nano","1936-0851","1936-086X","published","12","8","","7959","7966","2018","","","","AMER CHEMICAL SOC","","","","","","","10.1021/acsnano.8b02459","000443525600047","30016072","","urn:nbn:se:liu:diva-151513","","","dehalogenative homocoupling; gem-dibromomethyl; scanning tunneling microscopy; noncontact atomic force microscopy; surface chemistry","Materialkemi (10403)","","","<p>Funding Agencies|National Natural Science Foundation of China [21473123, 21622307, 21790351, 51403157, 21603045, 21425310, 91427301]; Fundamental Research Funds for the Central Universities of China [2018XKJC-009]; International Cooperation Training Project Funding for Postgraduate of Tonggji University [2018XKJC-009]; Alexander von Humboldt Foundation</p>","<p>Conductive polymers are of great importance in a variety of chemistry-related disciplines and applications. The recently developed bottom-up on-surface synthesis strategy provides us with opportunities for the fabrication of various nanostructures in a flexible and facile manner, which could be investigated by high-resolution microscopic techniques in real space. Herein, we designed and synthesized molecular precursors functionalized with benzal gem-dibromomethyl groups. A combination of scanning tunneling microscopy, noncontact atomic force microscopy, high-resolution synchrotron radiation photoemission spectroscopy, and density functional theory calculations demonstrated that it is feasible to achieve the direct formation of C-C double-bonded structural motifs via on-surface dehalogenative homocoupling reactions on the Au(111) surface. Correspondingly, we convert the sp(3)-hybridized state to an sp(2)-hybridized state of carbon atoms, i.e., from an alkyl group to an alkenyl one. Moreover, by such a bottom-up strategy, we have successfully fabricated poly(phenylenevinylene) chains on the surface, which is anticipated to inspire further studies toward understanding the nature of conductive polymers at the atomic scale.</p>","","","","","","","","","","","","","2018-09-24","2018-09-24","2018-09-24","","","18","","1","","","","","","false","","",""
"1250676","Greenberg, Eran (Tel Aviv Univ, Israel; Univ Chicago, IL 60637 USA);Leonov, Ivan (Inst Met Phys, Russia; NUST MISIS, Russia);Layek, Samar (Tel Aviv Univ, Israel);Konopkova, Zuzana (PETRA III, Germany);Pasternak, Moshe P. (Tel Aviv Univ, Israel);Dubrovinsky, Leonid (Univ Bayreuth, Germany);Jeanloz, Raymond (Univ Calif Berkeley, CA 94720 USA);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (NUST MISIS, Russia);Rozenberg, Gregory Kh. (Tel Aviv Univ, Israel)","Pressure-Induced Site-Selective Mott Insulator-Metal Transition in Fe2O3","Artikel i tidskrift","Refereegranskat","eng","Physical Review X","2160-3308","2160-3308","published","8","3","","","","2018","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevX.8.031059","000444211800001","","","urn:nbn:se:liu:diva-151474","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Israeli Science Foundation [1189/14]; U.S. Department of Energy; Swedish Research Council (VR) [2015-04391]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFOMatLiU) [2009 00971]; Swedish e-Science Research Centre (SeRC); Deutsche Forschungsgemeinschaft through Transregio [TRR 80]; Russian Science Foundation [18-12-00492]; Ministry of Education and Science of the Russian Federation [K3-2016-027]</p>","<p>We provide experimental and theoretical evidence for a pressure-induced Mott insulator-metal transition in Fe2O3 characterized by site-selective delocalization of the electrons. Density functional plus dynamical mean field theory (DFT + DMFT) calculations, along with Mossbauer spectroscopy, x-ray diffraction, and electrical transport measurements on Fe2O3 up to 100 GPa, reveal this site-selective Mott transition between 50 and 68 GPa, such that the metallization can be described by ((FE3+HS)-F-VI)(2)O-3 [R (3) over barc structure]-amp;gt;(50) (GPa) (Fe-VIII(3+HS) Fe-VI(M))O-3 [P2(1)/n structure]-amp;gt;(68 Gpa)(Fe-VI(M))(2)O-3[Aba2/PPv structure]. Within the P2(1)/n crystal structure, characterized by two distinct coordination sites (VI and VIII), we observe equal abundances of ferric ions (Fe3+) and ions having delocalized electrons (Fe-M), and only at higher pressures is a fully metallic high-pressure structure obtained, all at room temperature. Thereby, the transition is characterized by delocalization/metallization of the 3d electrons on half the Fe sites, with a site-dependent collapse of local moments. Above approximately 50 GPa, Fe2O3 is a strongly correlated metal with reduced electron mobility (large band renormalizations) of m*/m similar to 4 and 6 near the Fermi level. Importantly, upon decompression, we observe a site-selective (metallic) to conventional Mott insulator phase transition (Fe-VIII(3+HS) Fe-VI(M))O-3 -amp;gt;(50) (GPa)(Fe-VIII(3+HS) Fe-VI(3+HS))O-3 within the same P2(1)/n structure, indicating a decoupling of the electronic and lattice degrees of freedom. Our results offer a model for understanding insulator-metal transitions in correlated electron materials, showing that the interplay of electronic correlations and crystal structure may result in rather complex behavior of the electronic and magnetic states of such compounds.</p>","","","","","","","","","","","","","2018-09-24","2018-09-24","2018-10-19","http://liu.diva-portal.org/smash/get/diva2:1250676/FULLTEXT01.pdf","","9","","1","","","","","031059","false","","",""
"1259448","Gradov, O. M. (Russian Acad Sci, Russia);Stenflo, Lennart [lenst65] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Basic properties of nonlinear surface charge waves at a plasma boundary","Artikel i tidskrift","Refereegranskat","eng","Physics Letters A","0375-9601","1873-2429","published","42-43","","","3083","3085","2018","","","","ELSEVIER SCIENCE BV","","","","","","","10.1016/j.physleta.2018.08.018","000446145100006","","","urn:nbn:se:liu:diva-152052","","","Large amplitude oscillations; Plasma boundary; Solitary waves; Surface charge","Fusion, plasma och rymdfysik (10303)","","","","<p>The nonlinear properties of surface charges are here analyzed under ideal conditions. We thus deduce a new single equation from the wellknown equations which govern the cold electron plasma motion. Simple formulas that describe the propagation of surface charge perturbations along the plasma boundary are also found. (C) 2018 Elsevier B.V. All rights reserved.</p>","","","","","","","","","","","","","2018-10-29","2018-10-29","2018-10-29","","","2","","1","","","","","","false","","",""
"1256352","Stockem, Irina [irist97] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Max Planck Inst Eisenforsch GmbH, Germany);Bergman, Anders (Univ Versailles, France; CEA, France);Glensk, Albert (Max Planck Inst Eisenforsch GmbH, Germany);Hickel, Tilmann (Max Planck Inst Eisenforsch GmbH, Germany);Koermann, Fritz (Max Planck Inst Eisenforsch GmbH, Germany; Delft Univ Technol, Netherlands);Grabowski, Blazej (Max Planck Inst Eisenforsch GmbH, Germany);Neugebauer, Joerg (Max Planck Inst Eisenforsch GmbH, Germany);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Max Planck Inst Eisenforsch GmbH, Germany)","Anomalous Phonon Lifetime Shortening in Paramagnetic CrN Caused by Spin-Lattice Coupling: A Combined Spin and Ab Initio Molecular Dynamics Study","Artikel i tidskrift","Refereegranskat","eng","Physical Review Letters","0031-9007","1079-7114","published","121","12","","","","2018","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevLett.121.125902","000445326500007","30296117","","urn:nbn:se:liu:diva-151943","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|FP7 Marie Sklodowska-Curie COFUND Programme [600382]; priority programme SPP1599 ""Ferroic cooling"" [HI1300/6-2]; Netherlands Organisation for Scientific Research (NWO) under the VIDI research programme [15707]; European Research Council (ERC) under the EUs Horizon 2020 Research and Innovation Programme [639211]; Swedish Research Council (VR) [330-2014-6336]; Marie Sklodowska Curie Actions [INCA 600398]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFOMatLiU) [2009 00971]; Swedish Foundation for Strategic Research</p>","<p>We study the mutual coupling of spin fluctuations and lattice vibrations in paramagnetic CrN by combining atomistic spin dynamics and ab initio molecular dynamics. The two degrees of freedom are dynamically coupled, leading to nonadiabatic effects. Those effects suppress the phonon lifetimes at low temperature compared to an adiabatic approach. The dynamic coupling identified here provides an explanation for the experimentally observed unexpected temperature dependence of the thermal conductivity of magnetic semiconductors above the magnetic ordering temperature.</p>","","","","","","","","","","","","","2018-10-16","2018-10-16","2018-11-14","http://liu.diva-portal.org/smash/get/diva2:1256352/FULLTEXT01.pdf","","8","","2","","","","","125902","false","","",""
"1273226","Szymanski, N. J. (Univ Toledo, OH 43606 USA);Walters, L. N. (Northwestern Univ, IL 60208 USA);Hellman, Olle [olohe96] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (CALTECH, CA 91125 USA);Gall, D. (Rensselaer Polytech Inst, NY 12180 USA);Khare, S. V. (Univ Toledo, OH 43606 USA)","Dynamical stabilization in delafossite nitrides for solar energy conversion","Artikel i tidskrift","Refereegranskat","eng","Journal of Materials Chemistry A","2050-7488","","published","6","42","","20852","20860","2018","","","","ROYAL SOC CHEMISTRY","","","","","","","10.1039/c8ta07536k","000451600200029","","","urn:nbn:se:liu:diva-153534","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|National Science Foundation under CMMI [1629230, 1629239]; National Science Foundation under EFRI-2DARE program [1433467]; Air Force Research Laboratory, Space Vehicles Directorate [FA9453-11-C-0253]</p>","<p>Delafossite structured ternary nitrides, ABN(2), have been of recent experimental investigation for applications such as tandem solar and photoelectrochemical cells. We present a thorough first principles computational investigation of their stability, electronic structure, and optical properties. Nine compounds, where A = Cu, Ag, Au and B = V, Nb, Ta, were studied. For three of these compounds, CuTaN2, CuNbN2, and AgTaN2, our computations agree well with experimental results. Optimized lattice parameters, formation energies, and mechanical properties have been computed using the generalized gradient approximation (GGA). Phonon density of states computed at zero-temperature shows that all compounds are dynamically unstable at low temperatures. Including finite-temperature anharmonic effects stabilizes all compounds at 300 K, with the exception of AgVN2. Analysis of Crystal Orbital Hamiltonian Populations (COHP) provides insight into the bonding and antibonding characters of A-N and B-N pairs. Instability at low temperatures can be attributed to strong A-N antibonding character near the Fermi energy. B-N bonding is found to be crucial in maintaining stability of the structure. AgVN2 is the only compound to display significant B-N antibonding below the Fermi energy, as well as the strongest degree of A-N antibonding, both of which provide explanation for the sustained instability of this compound up to 900 K. Hybrid functional calculations of electronic and optical properties show that real static dielectric constants in the semiconductors are related to corresponding band gaps through the Moss relation. CuTaN2, CuNbN2, AgTaN2, AgNbN2, AgVN2, AuTaN2, and AuNbN2 exhibit indirect electronic band gaps while CuVN2 and AuVN2 are metallic. Imaginary parts of the dielectric function are characterized by d-d interband transitions in the semiconductors and d-d intraband transitions in the metals. Four compounds, CuTaN2, CuNbN2, AgTaN2, and AgNbN2, are predicted to exhibit large light absorption in the range of 1.0 to 1.7 eV, therefore making these materials good candidates for solar-energy conversion applications. Two compounds, AuTaN2 and AuNbN2, have band gaps and absorption onsets near the ideal range for obtaining high solar-cell conversion efficiency, suggesting that these compounds could become potential candidates as absorber materials in tandem solar cells or for band-gap engineering by alloying.</p>","","","","","","","","","","","","","2018-12-20","2018-12-20","2018-12-20","","","5","","1","","","","","","false","","",""
"1274648","Herriman, Jane E. (CALTECH, CA 91125 USA);Hellman, Olle [olohe96] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (CALTECH, CA 91125 USA);Fultz, Brent (CALTECH, CA 91125 USA)","Phonon thermodynamics and elastic behavior of GaN at high temperatures and pressures","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","98","21","","","","2018","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.98.214105","000452324400001","","","urn:nbn:se:liu:diva-153500","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Office of Science of the U.S. Department of Energy [DE-AC02-05CH11231]; Department of Energy through the Carnegie-DOE Alliance Centers Stewardship Sciences Academic Alliance Program; Department of Energy through Office of Science Graduate Fellowship Program (DOE SCGF) [DE-AC05-06OR23100]</p>","<p>The effects of temperature and pressure on the phonons of GaN were calculated for both the wurtzite and zinc-blende structures. The quasiharmonic approximation (QHA) gave reasonable results for the temperature dependence of the phonon DOS at zero pressure but unreliably predicted the combined effects of temperature and pressure. Pressure was found to change the explicit anharmonicity, altering the thermal shifts of phonons and more notably qualitatively changing the evolution of phonon lifetimes with increasing temperature. These effects were largest for the optical modes, and phonon frequencies below approximately 5 THz were adequately predicted with the QHA. The elastic anisotropies of GaN in both wurtzite and zinc-blende structures were calculated from the elastic constants as a function of pressure at 0 K. The elastic anisotropy increased with pressure until reaching elastic instabilities at 40 GPa (zinc blende) and 65 GPa (wurtzite). The calculated instabilities are consistent with proposed transformation pathways to rocksalt GaN and place upper bounds on the pressures at which wurtzite and zinc-blende GaN can be metastable.</p>","","","","","","","","","","","","","2019-01-02","2019-01-02","2019-03-25","http://liu.diva-portal.org/smash/get/diva2:1274648/FULLTEXT01.pdf","","3","","2","","","","","214105","false","","",""
"1276241","Hansson, Tobias [tobha84] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Brescia, Italy);Parra-Rivas, Pedro (Univ Libre Bruxelles, Belgium; Univ Leuven, Belgium);Bernard, Martino (Univ Brescia, Italy);Leo, Francois (Univ Libre Bruxelles, Belgium);Gelens, Lendert (Univ Leuven, Belgium);Wabnitz, Stefan (Univ Brescia, Italy; CNR INO, Italy)","Quadratic soliton combs in doubly resonant second-harmonic generation","Artikel i tidskrift","Refereegranskat","eng","Optics Letters","0146-9592","1539-4794","published","43","24","","6033","6036","2018","","","","OPTICAL SOC AMER","","","","","","","10.1364/OL.43.006033","000453212500033","30547998","","urn:nbn:se:liu:diva-153670","","","","Atom- och molekylfysik och optik (10302)","","","<p>Funding Agencies|H2020 Marie Sklodowska-Curie Actions (MSCA) [GA-2015-713694]; Vetenskapsradet (VR) [2017-05309]; Ministero dellIstruzione, dellUniversita e della Ricerca (MIUR) [2015KEZNYM-NEMO]; European Research Council (ERC) [757800]; KU Leuven</p>","<p>We report a theoretical investigation of quadratic frequency combs in a dispersive second-harmonic generation cavity system. We identify different dynamical regimes and demonstrate that the same system can exhibit both bright and dark localized cavity solitons in the absence of a temporal walk-off. (c) 2018 Optical Society of America</p>","","","","","","","","","","","","","2019-01-07","2019-01-07","2019-03-25","","","6","","2","","","","","","false","","",""
"1248044","Gambino, Davide [davga91] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Max Planck Inst Eisenforsch GmbH, Germany)","Lattice relaxations in disordered Fe-based materials in the paramagnetic state from first principles","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","98","6","","","","2018","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.98.064105","000443139600004","","","urn:nbn:se:liu:diva-151199","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Swedish Research Council (VR) [2014-6336]; Marie Sklodowska Curie Actions, Cofund [INCA 600398]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFOMatLiU) [2009 00971]; Swedish Foundation for Strategic Research</p>","<p>The first-principles calculation of many material properties, in particular related to defects and disorder, starts with the relaxation of the atomic positions of the system under investigation. This procedure is routine for nonmagnetic and magnetically ordered materials. However, when it comes to magnetically disordered systems, in particular the paramagnetic phase of magnetic materials, it is not clear how the relaxation procedure should be performed or which geometry should be used. Here we propose a method for the structural relaxation of magnetic materials in the paramagnetic regime, in an adiabatic fast-magnetism approximation within the disordered local moment (DLM) picture in the framework of density functional theory. The method is straightforward to implement using any ab initio code that allows for structural relaxations. We illustrate the importance of considering the disordered magnetic state during lattice relaxations by calculating formation energies and geometries for an Fe vacancy and C insterstitial atom in body-centered cubic (bcc) Fe as well as bcc Fe1-xCrx random alloys in the paramagnetic state. In the vacancy case, the nearest neighbors to the vacancy relax toward the vacancy of 0.14 angstrom (-5% of the ideal bcc nearest-neighbor distance), which is twice as large as the relaxation in the ferromagnetic case. The vacancy formation energy calculated in the DLM state on these positions is 1.60 eV, which corresponds to a reduction of about 0.1 eV compared to the formation energy calculated using DLM but on ferromagnetic-relaxed positions. The carbon interstitial formation energy is found to be 0.41 eV when the DLM relaxed positions are used, as compared to 0.59 eV when the FM-relaxed positions are employed. For bcc Fe0.5Cr0.5 alloys, the mixing enthalpy is reduced by 5 meV/atom, or about 10%, when the DLM state relaxation is considered, as compared to positions relaxed in the ferromagnetic state.</p>","","","","","","","","","","","","","2018-09-13","2018-09-13","2019-05-14","http://liu.diva-portal.org/smash/get/diva2:1248044/FULLTEXT01.pdf","","2","","2","urn:nbn:se:liu:diva-156835","","","","064105","false","","",""
"1184538","Ribeiro Jr, Luiz Antonio [luiri41] [0000-0001-7468-2946] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Institute of Physics, University of Brasίlia, Brasίlia, Brazil);da Silva, Gesiel Gomes (Institute of Physics, University of Brasίlia, Brasίlia, Brazil; Goias Federal Institute of Science and Technology, IFG, Luziânia, Brazil);de Sousa Jr, Rafael Timoteo (Department of Electrical Engineering, University of Brasίlia, Brasίlia, Brazil);de Almeida Fonseca, Antonio Luciano (Institute of Physics, University of Brasίlia, Brasίlia, Brazil);da Cunha, Wiliam Ferreira (Institute of Physics, University of Brasίlia, Brasίlia, Brazil);Magela e Silva, Geraldo (Institute of Physics, University of Brasίlia, Brasίlia, Brazil)","Spin-Orbit Effects on the Dynamical Properties of Polarons in Graphene Nanoribbons","Artikel i tidskrift","Refereegranskat","eng","Scientific Reports","2045-2322","2045-2322","published","8","","","","","2018","","","","Nature Publishing Group","","","","","","","10.1038/s41598-018-19893-y","000423508900085","29382862","2-s2.0-85041342699","urn:nbn:se:liu:diva-145247","","","","Annan fysik (10399)","","","<p>Funding Agencies|CNPq; CAPES; FAP-DF; FINATEC; Brazilian Ministry of Planning, Development and Management [005/2016 DIPLA, 11/2016 SEST]; DPGU - Brazilian Union Public Defender [066/2016]; FAP-DF [0193.000.942/2015, 0193.001343/2016]; IFG</p>","<p>The dynamical properties of polarons in armchair graphene nanoribbons (GNR) is numerically investigated in the framework of a two-dimensional tight-binding model that considers spin-orbit (SO) coupling and electron-lattice (e-l) interactions. Within this physical picture, novel polaron properties with no counterparts to results obtained from conventional tight-binding models are obtained. Our findings show that, depending on the systems width, the presence of SO coupling changes the polarons charge localization giving rise to different degrees of stability for the charge carrier. For instance, the joint action of SO coupling and e-l interactions could promote a slight increase on the charge concentration in the center of the lattice deformation associated to the polaron. As a straightforward consequence, this process of increasing stability would lead to a depreciation in the polarons motion by decreasing its saturation velocity. Our finds are in good agreement with recent experimental investigations for the charge localization in GNR, mostly when it comes to the influence of SO coupling. Moreover, the contributions reported here provide a reliable method for future works to evaluate spin-orbit influence on the performance of graphene nanoribbons.</p>","","","","","","","","","","","","","2018-02-21","2018-02-21","2019-06-27","http://liu.diva-portal.org/smash/get/diva2:1184538/FULLTEXT01.pdf","","6","","1","","","","","1914","true","","",""
"1182444","Rivera Vila, Henrique Vieira (Univ Brasilia, Brazil);Ribeiro, Luiz Antonio [luiri41] [0000-0001-7468-2946] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Brasilia, Brazil);Machado de Macedo, Luiz Guilherme (Fed Univ Para, Brazil);Gargano, Ricardo (Univ Brasilia, Brazil)","On the Angular Distribution of the H+Li-2 Cross Sections: a Converged Time-Independent Quantum Scattering Study","Artikel i tidskrift","Refereegranskat","eng","Scientific Reports","2045-2322","2045-2322","published","8","","","","","2018","","","","NATURE PUBLISHING GROUP","","","","","","","10.1038/s41598-018-19233-0","000422739300007","29348595","","urn:nbn:se:liu:diva-145143","","","","Annan fysik (10399)","","","<p>Funding Agencies|CNPQ; Brazilian Ministry of Planning, Budget and Management [DIPLA 005/2016]; FAPDF [0193.000942/2015]</p>","<p>A thorough time-independent quantum scattering study is performed on a benchmark potential energy surface for the H+Li-2 reaction at the fundamental electronic state. Integral and differential cross sections are calculated along with thermal rate coefficients until convergence is reached. Our findings show that vibrational and rotational excitations of the reactant hinder reactivity, though for the latter a considerable reaction promotion was spotted as we increase the reactant rotational quantum number until the critical value of j = 4. Such a promotion then begins to retract, eventually becoming an actual inhibition for larger j. In a straightforward manner, the concept of time-independent methods implemented in this study allowed this accurate state-to-state analysis. Furthermore, a nearly isotropic behaviour of the scattering is noted to take place from the angular point of view. Remarkably, our computational protocol is ideally suited to yield converged thermal rate coefficients, revealing a non-Arrhenius pattern and showing that J-shifting approach fails to describe this particular reaction. Our results, when compared to previous and independent ones, reinforce the latest theoretical reference for future validation in the experimental field.</p>","","","","","","","","","","","","","2018-02-13","2018-02-13","2019-06-27","http://liu.diva-portal.org/smash/get/diva2:1182444/FULLTEXT01.pdf","","4","","1","","","","","1044","false","","",""
"1209542","Ribeiro, Luiz Antonio [luiri41] [0000-0001-7468-2946] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Brasilia, Brazil);Monteiro, Fabio Ferreira (Univ Brasilia, Brazil);Enders, Bernhard Georg (Univ Brasilia, Brazil);de Almeida Fonseca, Antonio Luciano (Univ Brasilia, Brazil);Magela e Silva, Geraldo (Univ Brasilia, Brazil);da Cunha, Wiliam Ferreira (Univ Brasilia, Brazil)","Dynamic Formation of Bipolaron-Exciton Complexes in Conducting Polymers","Artikel i tidskrift","Refereegranskat","eng","Journal of Physical Chemistry A","1089-5639","1520-5215","published","122","15","","3866","3872","2018","","","","AMER CHEMICAL SOC","","","","","","","10.1021/acs.jpca.7b12185","000430783700018","29608859","","urn:nbn:se:liu:diva-147933","","","","Annan kemi (10499)","","","<p>Funding Agencies|Brazilian Research Council CNPq; Brazilian Research Council CAPES; Brazilian Research Council FAP-DF; Brazilian Research Council FINATEC; CENAPAD-SP; FAP-DF [193.001.234/2016, 193.001.556/2017, 0193.000.942/2015]; Brazilian Ministry of Planning, Budget and Management [DIPLA 005/2016]</p>","<p>The recombination dynamics of two oppositely charged bipolarons within a single polymer chain is numerically studied in the scope of a one-dimensional tight-binding model that considers electron electron and electron-phonon (e-ph) interactions. By scanning among values of e-ph coupling and electric field, novel channels for the bipolaron recombination were yielded based on the interplay between these two parameters. The findings point to the formation of a compound species formed from the coupling between a bipolaron and an exciton. Depending on the electric field and e-ph coupling strengths, the recombination mechanism may yield two distinct products: a trapped (and almost neutral) or a moving (and partially charged) bipolaron-exciton. These results might enlighten the understanding of the electroluminescence processes in organic light-emitting devices.</p>","","","","","","","","","","","","","2018-05-23","2018-05-23","2019-06-27","","","6","","2","","","","","","false","","",""
"1209556","Ribeiro, Luiz Antonio [luiri41] [0000-0001-7468-2946] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Monteiro, Fabio Ferreira (Univ Brasilia, Brazil);da Cunha, Wiliam Ferreira (Univ Florida, FL 32611 USA);Magela e Silva, Geraldo (Univ Brasilia, Brazil)","Charge Carrier Scattering in Polymers: A New Neutral Coupled Soliton Channel","Artikel i tidskrift","Refereegranskat","eng","Scientific Reports","2045-2322","2045-2322","published","8","","","","","2018","","","","NATURE PUBLISHING GROUP","","","","","","","10.1038/s41598-018-24948-1","000430919900044","29700347","","urn:nbn:se:liu:diva-147925","","","","Annan fysik (10399)","","","<p>Funding Agencies|Brazilian Research Council CNPq; Brazilian Research Council CAPES; Brazilian Research Council FINATEC; Brazilian Research Council FAPDF grant [0193.000942/2015]; Brazilian Ministry of Planning, Budget and Management [DIPLA 005/2016]</p>","<p>The dynamical scattering of two oppositely charged bipolarons in non-degenerate organic semiconducting lattices is numerically investigated in the framework of a one-dimensional tight-biding-Hubbard model that includes lattice relaxation. Our findings show that it is possible for the bipolaron pair to merge into a state composed of a confined soliton-antisoliton pair, which is characterized by the appearance of states within less than 0.1 eV from the Fermi level. This compound is in a narrow analogy to a meson confining a quark-antiquark pair. Interestingly, solitons are quasi-particles theoretically predicted to arise only in polymer lattices with degenerate ground state: in the general case of nondegenerate ground state polymers, isolated solitons are not allowed.</p>","","","","","","","","","","","","","2018-05-23","2018-05-23","2019-06-27","http://liu.diva-portal.org/smash/get/diva2:1209556/FULLTEXT01.pdf","","4","","1","","","","","6595","false","","",""
"1234401","Silva, Gesiel Gomes (Goias Fed Inst Educ Sci and Technol, Brazil; Univ Brasilia, Brazil);da Cunha, Wiliam Ferreira (Univ Brasilia, Brazil);de Sousa Junior, Rafael Timoteo (Univ Brasilia, Brazil);Almeida Fonseca, Antonio Luciano (Univ Brasilia, Brazil);Ribeiro, Luiz Antonio [luiri41] [0000-0001-7468-2946] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Brasilia, Brazil);Magela e Silva, Geraldo (Univ Brasilia, Brazil)","Influence of quasi-particle density over polaron mobility in armchair graphene nanoribbons","Artikel i tidskrift","Refereegranskat","eng","Physical Chemistry, Chemical Physics - PCCP","1463-9076","1463-9084","published","20","24","","16712","16718","2018","","","","ROYAL SOC CHEMISTRY","","","","","","","10.1039/c8cp02373e","000436032900042","29878013","","urn:nbn:se:liu:diva-149710","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|CNPq; CAPES; FAP-DF; CENAPAD-SP; Brazilian Ministry of Planning, Development and Management [005/2016, 11/2016]; DPGU - Brazilian Union Public Defender [066/2016]; FAP-DF [0193.000.942/2015, 193.001.511/2017]</p>","<p>An important aspect concerning the performance of armchair graphene nanoribbons (AGNRs) as materials for conceiving electronic devices is related to the mobility of charge carriers in these systems. When several polarons are considered in the system, a quasi-particle wave function can be affected by that of its neighbor provided the two are close enough. As the overlap may affect the transport of the carrier, the question concerning how the density of polarons affect its mobility arises. In this work, we investigate such dependence for semiconducting AGNRs in the scope of nonadiabatic molecular dynamics. Our results unambiguously show an impact of the density on both the stability and average velocity of the quasi-particles. We have found a phase transition between regimes where increasing density stops inhibiting and starts promoting mobility; densities higher than 7 polarons per 45 angstrom present increasing mean velocity with increasing density. We have also established three different regions relating electric field and average velocity. For the lowest electric field regime, surpassing the aforementioned threshold results in overcoming the 0.3 angstrom fs(-1) limit, thus representing a transition between subsonic and supersonic regimes. For the highest of the electric fields, density effects alone are responsible for a stunning difference of 1.5 angstrom fs(-1) in the mean carrier velocity.</p>","","","","","","","","","","","","","2018-07-24","2018-07-24","2019-06-27","http://liu.diva-portal.org/smash/get/diva2:1234401/FULLTEXT01.pdf","","6","","2","","","","","","false","true","",""
"1213611","Sangiovanni, Davide [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Ruhr Univ Bochum, Germany)","Inherent toughness and fracture mechanisms of refractory transition-metal nitrides via density-functional molecular dynamics","Artikel i tidskrift","Refereegranskat","eng","Acta Materialia","1359-6454","1873-2453","published","151","","","11","20","2018","","","","PERGAMON-ELSEVIER SCIENCE LTD","","","","","","","10.1016/j.actamat.2018.03.038","000432760300002","","","urn:nbn:se:liu:diva-148240","","","Refractory transition-metal nitrides; Ab initio molecular dynamics; Toughness; Fracture; Electronic structures","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Olle Engkvist Foundation</p>","<p>Hard refractory transition-metal nitrides possess unique combinations of outstanding mechanical and physical properties, but are typically brittle. Recent experimental results demonstrated that single-crystal NaCI-structure (B1) V0.5Mo0.5N pseudobinary solid solutions are both hard (similar to 20 GPa) and ductile; that is, they exhibit toughness, which is unusual for ceramics. However, key atomic-scale mechanisms underlying this inherent toughness are unknown. Here, I carry out density-functional ab initio molecular dynamics (AIMD) simulations at room temperature to identify atomistic processes and associated changes in the electronic structure which control strength, plasticity, and fracture in V0.5Mo0.5N, as well as reference B1 TiN, subject to amp;lt;001amp;gt; and amp;lt;110amp;gt; tensile deformation. AIMD simulations reveal that V0.5Mo0.5N is considerably tougher than TiN owing to its ability to (i) isotropically redistribute mechanical stresses within the elastic regime, (ii) dissipate the accumulated strain energy by activating local structural transformations beyond the yield point. In direct contrast, TiN breaks in brittle manner when applied stresses reach its tensile strength. Charge transfer maps show that the adaptive mechanical response of V0.5Mo0.5N originates from highly populated d-d metallic-states, which allow for counterbalancing the destabilization induced via tensile deformation by enabling formation of new chemical bonds. The high ionic character and electron-localization in TiN precludes the possibility of modifying bonding geometries to accommodate the accumulated stresses, thus suddenly causing materials fracture for relatively low strain values. </p>","","","","","","","","","","","","","2018-06-05","2018-06-05","2019-06-28","","","1","","2","","","","","","false","","",""
"1217881","Sangiovanni, Davide Giuseppe [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Copper adatom, admolecule transport, and island nucleation on TiN(0 0 1) via <em>ab initio</em> molecular dynamics","Artikel i tidskrift","Refereegranskat","eng","Applied Surface Science","0169-4332","1873-5584","published","50","","","180","189","2018","","","","Elsevier","","","","","","","10.1016/j.apsusc.2018.04.191","000433199000021","","","urn:nbn:se:liu:diva-148576","","","","Kemi (104);Den kondenserade materiens fysik (10304)","","","<p>Funding agencies: Olle Engkvist Foundation</p>","<p>Density-functional <em>ab initio</em> molecular dynamics (AIMD) simulations are carried out to determine Cu adatom and admolecule transport properties as a function of temperature, as well as atomistic processes leading to formation of Cu/TiN(0 0 1) islands at 350 K. At very low temperatures <em>T</em> ≤ 200 K, Cu adatoms (Cuad) migrate among favored fourfold-hollow surface sites by passing across atop-Ti metastable positions. For increasing temperatures, however, Cuad transport becomes progressively more isotropic, and switches continuously from normal- to super-diffusive with mean-square displacement dependencies on time that alternate between linear and exponential. Despite that, the Cuad diffusivity <em>D</em> can be expressed by a fairly Arrhenius-like behavior <em>D</em>(<em>T</em>) = 8.26(×2±1) × 10−4 cm2 s−1exp[(−0.04 ± 0.01 eV)/(<em>k</em>B<em>T</em>)] over the entire investigated temperature range (100 ≤ <em>T</em> ≤ 1000 K). AIMD simulations also reveal that the condensation of Cu adatoms into Cux>1 adspecies is kinetically hindered by long-range (>5.5 Å) adatom/adatom repulsion. During Cu island nucleation, all Cu atoms occupy atop-N positions indicating favored Cu(0 0 1)/TiN(0 0 1) epitaxial growth. Nevertheless, Cu agglomerates formed by five, or more, atoms tend to arrange in 3D structures, which maximize intracluster bonds while minimizing film/substrate interactions. Results here presented provide insights for understanding the properties of weakly-interacting metal/substrate interface systems in general.</p>","","","","","","","","","","","","","2018-06-13","2018-06-13","2019-06-28","","","1","","1","","","","","","false","","",""
"1188371","Edström, Daniel [daned22] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Sangiovanni, Davide [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Ruhr Univ Bochum, Germany);Hultman, Lars [larhu75] [0000-0002-2837-3656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Petrov, Ivan [ivape26] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Illinois, IL 61801 USA);Greene, Joseph E [josgr17] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Univ Illinois, IL 61801 USA);Chirita, Valeriu [valch35] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Elastic properties and plastic deformation of TiC- and VC-based alloys","Artikel i tidskrift","Refereegranskat","eng","Acta Materialia","1359-6454","1873-2453","published","144","","","376","385","2018","","","","PERGAMON-ELSEVIER SCIENCE LTD","","","","","","","10.1016/j.actamat.2017.10.047","000424067100035","","","urn:nbn:se:liu:diva-145470","","","Carbides; Density functional theory; Elastic properties; Ductility; Toughness","Annan materialteknik (20599)","","","<p>Funding Agencies|Swedish Research Council (VR) Linkoping Linnaeus Initiative LiLi-NFM [2008-6572]; Swedish Government Strategic Research Area Grant in Materials Science on Advanced Functional Materials (Grant SFO-Mat-LiU) [2009 00971]; Olle Engkvist Foundation</p>","<p>Transition-metal (TM) carbides are an important class of hard, protective coating materials; however, their brittleness often limits potential applications. We use density functional theory to investigate the possibility of improving ductility by forming pseudobinary cubic (MMC)-M-1-C-2 alloys, for which M-1 = Ti or V and M-2 = W or Mo. The alloying elements are chosen based on previous results showing improved ductility of the corresponding pseudobinary nitride alloys with respect to their parent compounds. While commonly-used empirical criteria do not indicate enhanced ductility in the carbide alloys, calculated stress/strain curves along known slip systems, supported by electronic structure analyses, indicate ductile behavior for VMoC. As VMoC layers are sheared along the 1 (1) over bar0 direction on {111} planes, the stress initially increases linearly up to a yield point where the accumulated stress is partially dissipated. With further increase in strain, the stress increases again until fracture occurs. A similar mechanical behavior is observed for the corresponding TM nitride VMoN, known to be a ductile ceramic material [1]. Thus, our results show that VMoC is a TM carbide alloy which may be both hard and ductile, i.e. tough. (C) 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.</p>","","","","","","","","","","","","","2018-03-07","2018-03-07","2019-06-28","","","6","","2","","","","","","false","","",""
"1176706","Sangiovanni, Davide [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Ruhr University of Bochum, Germany);Mei, A. B. (University of Illinois, IL 61801 USA; Cornell University, NY 14853 USA);Edström, Daniel [daned22] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Hultman, Lars [larhu75] [0000-0002-2837-3656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Chirita, Valeriu [valch35] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Petrov, Ivan [ivape26] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (University of Illinois, USA);Greene, Joseph E [josgr17] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (University of Illinois, USA)","Effects of surface vibrations on interlayer mass transport: Ab initio molecular dynamics investigation of Ti adatom descent pathways and rates from TiN/TiN(001) islands","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","97","3","","","","2018","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.97.035406","000419320900005","","","urn:nbn:se:liu:diva-144438","","","","Teoretisk kemi (10407)","","","<p>Funding Agencies|Olle Engkvist Foundation [2016/408]; Swedish Research Council (VR) Linkoping Linnaeus Initiative (LiLi-NFM) [2008-6572, 2014-5790, 2013-4018]; Swedish Government Strategic Research Area Grant in Materials Science on Advanced Functional Materials (Swedenapos;s innovation agency VINNOVA) [MatLiU 2009-00971]; Knut and Alice Wallenberg Foundation [2011.0094]</p>","<p>We carried out density-functional ab initio molecular dynamics (AIMD) simulations of Ti adatom (Ti-ad ) migration on, and descent from, square TiN(100) epitaxial islands on TiN(001) at temperatures (T) ranging from 1200 to 2400 K. Adatom-descent energy barriers determined via ab initio nudged-elastic-band calculations at 0 Kelvin suggest that Ti interlayer transport on TiN(001) occurs essentially exclusively via direct hopping onto a lower layer. However, AIMD simulations reveal comparable rates for Ti-ad descent via direct hopping vs push-out/exchange with a Ti island-edge atom for T amp;gt;= 1500 K. We demonstrate that this effect is due to surface vibrations, which yield considerably lower activation energies at finite temperatures by significantly modifying the adatom push-out/exchange reaction pathway.</p>","","","","","","","","","","","","","2018-01-23","2018-01-23","2019-06-28","http://liu.diva-portal.org/smash/get/diva2:1176706/FULLTEXT01.pdf","","7","","2","","","","","035406","false","","",""
"1236450","Sangiovanni, Davide Giuseppe [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Ruhr Univ Bochum, Germany);Kostov Gueorguiev, Gueorgui [guegu96] [0000-0001-9402-1491] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Kakanakova-Georgieva, Anelia [aneka59] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Ab initio molecular dynamics of atomic-scale surface reactions: insights into metal organic chemical vapor deposition of AlN on graphene","Artikel i tidskrift","Refereegranskat","eng","Physical Chemistry, Chemical Physics - PCCP","1463-9076","1463-9084","published","20","26","","17751","17761","2018","","","","Royal Society of Chemistry","","","","","","","10.1039/c8cp02786b","000437473300021","29915819","","urn:nbn:se:liu:diva-149847","","","","Materialkemi (10403)","","","<p>Funding Agencies|Swedish Research Council (VR) through FLAG-ERA JTC project GRIFONE [VR 2015-06816, VR 2017-04071]; Olle Engkvist Foundation</p>","<p>Metal organic chemical vapor deposition (MOCVD) of group III nitrides on graphene heterostructures offers new opportunities for the development of flexible optoelectronic devices and for the stabilization of conceptually-new two-dimensional materials. However, the MOCVD of group III nitrides is regulated by an intricate interplay of gas-phase and surface reactions that are beyond the resolution of experimental techniques. We use density-functional ab initio molecular dynamics (AIMD) with van der Waals corrections to identify atomistic pathways and associated electronic mechanisms driving precursor/surface reactions during metal organic vapor phase epitaxy at elevated temperatures of aluminum nitride on graphene, considered here as model case study. The results presented provide plausible interpretations of atomistic and electronic processes responsible for delivery of Al, C adatoms, and C-Al, CHx, AlNH2 admolecules on pristine graphene via precursor/surface reactions. In addition, the simulations reveal C adatom permeation across defect-free graphene, as well as exchange of C monomers with graphene carbon atoms, for which we obtain rates of approximate to 0.3 THz at typical experimental temperatures (1500 K), and extract activation energies Eexca = 0.28 +/- 0.13 eV and attempt frequencies A(exc) = 2.1 (x1.7(+/- 1)) THz via Arrhenius linear regression. The results demonstrate that AIMD simulations enable understanding complex precursor/surface reaction mechanisms, and thus propose AIMD to become an indispensable routine prediction-tool toward more effective exploitation of chemical precursors and better control of MOCVD processes during synthesis of functional materials.</p>","","","","","","","","","","","","","2018-08-02","2018-08-02","2019-06-28","http://liu.diva-portal.org/smash/get/diva2:1236450/FULLTEXT01.pdf","","3","","2","","","","","","false","true","",""
"1297725","Pourovskii, L. V. (Univ Paris Saclay, France; Coll France, France; Natl Univ Sci and Technol MISIS, Russia);Mravlje, J. (Jozef Stefan Inst, Slovenia);Georges, A. (Univ Paris Saclay, France; Coll France, France; Univ Geneva, Switzerland);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia)","Correction: Electron-electron scattering and thermal conductivity of epsilon-iron at Earths core conditions (vol 19, 073022, 2017)","Artikel i tidskrift","Refereegranskat","eng","New Journal of Physics","1367-2630","1367-2630","published","20","","","","","2018","","","","IOP PUBLISHING LTD","","","","","http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-140525","","10.1088/1367-2630/aae6e1","000460100100001","","","urn:nbn:se:liu:diva-155623","","","","Fysik (103)","","","","<p>n/a</p>","","","","","","","","","","","","","2019-03-20","2019-03-20","2019-08-29","http://liu.diva-portal.org/smash/get/diva2:1297725/FULLTEXT01.pdf","","5","","1","","","","","109501","false","","",""
"1209622","Berggren, Karl-Fredrik [karbe79] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Tellander, Felix (Lund Univ, Sweden);Yakymenko, Iryna [iryya88] [0000-0001-6635-3130] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Basic modelling of transport in 2D wave-mechanical nanodots and billiards with balanced gain and loss mediated by complex potentials","Artikel i tidskrift","Refereegranskat","eng","Journal of Physics: Condensed Matter","0953-8984","1361-648X","published","30","20","","","","2018","","","","IOP PUBLISHING LTD","","","","","","","10.1088/1361-648X/aabbfc","000431067600001","29620539","","urn:nbn:se:liu:diva-147905","","","open quantum dots; transport; non-Hermitian quantum mechanics; parity-time symmetry; symmetry breaking; exceptional points; musical instruments","Annan fysik (10399)","","","","<p>Non-Hermitian quantum mechanics with parity-time (PT) symmetry is presently gaining great interest, especially within the fields of photonics and optics. Here, we give a brief overview of low-dimensional semiconductor nanodevices using the example of a quantum dot with input and output leads, which are mimicked by imaginary potentials for gain and loss, and how wave functions, particle flow, coalescence of levels and associated breaking of PT symmetry may be analysed within such a framework. Special attention is given to the presence of exceptional points and symmetry breaking. Related features for musical string instruments and wolf-notes are outlined briefly with suggestions for further experiments.</p>","","","","","","","","","","","","","2018-05-23","2018-05-23","2019-09-24","http://liu.diva-portal.org/smash/get/diva2:1209622/FULLTEXT01.pdf","","3","","1","","","","","204003","false","","",""
"1209624","Karlsson, H. [n/a] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Yakymenko, Iryna [iryya88] [0000-0001-6635-3130] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Berggren, Karl-Fredrik [karbe79] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Nature of magnetization and lateral spin-orbit interaction in gated semiconductor nanowires","Artikel i tidskrift","Refereegranskat","eng","Journal of Physics: Condensed Matter","0953-8984","1361-648X","published","30","21","","","","2018","","","","IOP PUBLISHING LTD","","","","","","","10.1088/1361-648X/aabc15","000431423400002","29623898","","urn:nbn:se:liu:diva-147904","","","quantum wire; quantum transport; lateral spin-orbit interaction; modelling; Hartree-Fock method","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Carl Trygger Science Foundation of Sweden</p>","<p>Semiconductor nanowires are interesting candidates for realization of spintronics devices. In this paper we study electronic states and effects of lateral spin-orbit coupling (LSOC) in a one-dimensional asymmetrically biased nanowire using the Hartree-Fock method with Dirac interaction. We have shown that spin polarization can be triggered by LSOC at finite source-drain bias,as a result of numerical noise representing a random magnetic field due to wiring or a random background magnetic field by Earth magnetic field, for instance. The electrons spontaneously arrange into spin rows in the wire due to electron interactions leading to a finite spin polarization. The direction of polarization is, however, random at zero source-drain bias. We have found that LSOC has an effect on orientation of spin rows only in the case when source-drain bias is applied.</p>","","","","","","","","","","","","","2018-05-23","2018-05-23","2019-09-24","","","3","","1","","","","","215302","false","","",""
"1211310","Ekeroth, Sebastian [sebek07] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Plasma och beläggningsfysik [2225]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Münger, Peter [petmu26] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Boyd, Robert [robbo87] [0000-0002-6602-7981] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Plasma och beläggningsfysik [2225]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ekspong, Joakim (Umeå Univ, Sweden);Wågberg, Thomas (Umeå Univ, Sweden);Edman, Ludvig (Umeå Univ, Sweden);Brenning, Nils [nilbr83] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Plasma och beläggningsfysik [2225]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (KTH Royal Inst Technol, Sweden);Helmersson, Ulf [ulfhe30] [0000-0002-1744-7322] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Plasma och beläggningsfysik [2225]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Catalytic Nanotruss Structures Realized by Magnetic Self-Assembly in Pulsed Plasma","Artikel i tidskrift","Refereegranskat","eng","Nano letters (Print)","1530-6984","1530-6992","published","18","5","","3132","3137","2018","","","","American Chemical Society (ACS)","","","","","","","10.1021/acs.nanolett.8b00718","000432093200055","29624405","","urn:nbn:se:liu:diva-148107","","","Nanotrusses; nanowires; nanoparticles; iron; electrocatalysis; pulsed sputtering","Materialkemi (10403)","","","","<p>Tunable nanostructures that feature a high surface area are firmly attached to a conducting substrate and can be fabricated efficiently over significant areas, which are of interest for a wide variety of applications in, for instance, energy storage and catalysis. We present a novel approach to fabricate Fe nanoparticles using a pulsed-plasma process and their subsequent guidance and self-organization into well-defined nanostructures on a substrate of choice by the use of an external magnetic field. A systematic analysis and study of the growth procedure demonstrate that nondesired nanoparticle agglomeration in the plasma phase is hindered by electrostatic repulsion, that a polydisperse nanoparticle distribution is a consequence of the magnetic collection, and that the formation of highly networked nanotruss structures is a direct result of the polydisperse nanoparticle distribution. The nanoparticles in the nanotruss are strongly connected, and their outer surfaces are covered with a 2 nm layer of iron oxide. A 10 mu m thick nanotruss structure was grown on a lightweight, flexible and conducting carbon-paper substrate, which enabled the efficient production of H-2 gas from water splitting at a low overpotential of 210 mV and at a current density of 10 mA/cm(2).</p>","","","","","","","","","","","","","2018-05-30","2018-05-30","2019-11-11","http://liu.diva-portal.org/smash/get/diva2:1211310/FULLTEXT01.pdf","Knut och Alice Wallenbergs Stiftelse [KAW 14.0276]","8","","2","urn:nbn:se:liu:diva-161300","","","","","false","","",""
"1172548","Gharavi, Mohammad Amin [mohgh20] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Armiento, Rickard [ricar47] [0000-0002-5571-0814] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Max Planck Institute Eisenforsch GmbH, Germany);Eklund, Per [perek02] [0000-0003-1785-0864] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Theoretical study of phase stability, crystal and electronic structure of MeMgN2 (Me = Ti, Zr, Hf) compounds","Artikel i tidskrift","Refereegranskat","eng","Journal of Materials Science","0022-2461","1573-4803","published","53","6","","4294","4305","2018","","","","SPRINGER","","","","","","","10.1007/s10853-017-1849-0","000418294200030","","","urn:nbn:se:liu:diva-144130","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|European Research Council under the European Communitys Seventh Framework Programme (FP)/ERC [335383]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; Swedish Foundation for Strategic Research (SSF) through the Future Research Leaders 5 and 6 programs; Knut and Alice Wallenberg foundation through the Academy Fellow program; Swedish Research Council (VR) [621-2012-4430, 2016-03365]; Swedish Research Council (VR) through International Career Grant [330-2014-6336]; Marie Sklodowska Curie Actions, Cofund [INCA 600398]; VR Grant [2016-04810]; Swedish e-Science Research Centre (SeRC)</p>","<p>Scandium nitride has recently gained interest as a prospective compound for thermoelectric applications due to its high Seebeck coefficient. However, ScN also has a relatively high thermal conductivity, which limits its thermoelectric efficiency and figure of merit (zT). These properties motivate a search for other semiconductor materials that share the electronic structure features of ScN, but which have a lower thermal conductivity. Thus, the focus of our study is to predict the existence and stability of such materials among inherently layered equivalent ternaries that incorporate heavier atoms for enhanced phonon scattering and to calculate their thermoelectric properties. Using density functional theory calculations, the phase stability of TiMgN2, ZrMgN2 and HfMgN2 compounds has been calculated. From the computationally predicted phase diagrams for these materials, we conclude that all three compounds are stable in these stoichiometries. The stable compounds may have one of two competing crystal structures: a monoclinic structure (LiUN2 prototype) or a trigonal superstructure (NaCrS2 prototype; RmH). The band structure for the two competing structures for each ternary is also calculated and predicts semiconducting behavior for all three compounds in the NaCrS2 crystal structure with an indirect band gap and semiconducting behavior for ZrMgN2 and HfMgN2 in the monoclinic crystal structure with a direct band gap. Seebeck coefficient and power factors are also predicted, showing that all three compounds in both the NaCrS2 and the LiUN2 structures have large Seebeck coefficients. The predicted stability of these compounds suggests that they can be synthesized by, e.g., physical vapor deposition.</p>","","","","","","","","","","","","","2018-01-10","2018-01-10","2019-11-18","http://liu.diva-portal.org/smash/get/diva2:1172548/FULLTEXT01.pdf","","4","","1","urn:nbn:se:liu:diva-162020","","","","","false","","",""
"1251748","Ekholm, Marcus [marek10] [0000-0002-7563-1494] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Gambino, Davide [davga91] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Jönsson, Johan [johjo06] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Tasnadi, Ferenc [ferta55] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Max Planck Inst Eisenforsch GmbH, Germany);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia)","Assessing the SCAN functional for itinerant electron ferromagnets","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","98","9","","","","2018","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.98.094413","000444348500004","","","urn:nbn:se:liu:diva-151640","","","","Teoretisk kemi (10407)","","","<p>Funding Agencies|Swedish e-Science Research Centre (SeRC); Swedish Research Council (VR) through the International Career Grant [20146336]; Marie Sklodowska CurieActions, Cofund, Project [INCA 600398]; Swedish Foundation for Strategic Research (SSF) through the Future Research Leaders 6 program; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; competence center FunMat-II - Vinnova [201605156]; Russian Science Foundation [18-12-00492]</p>","<p>Density functional theory is a standard model for condensed-matter theory and computational material science. The accuracy of density functional theory is limited by the accuracy of the employed approximation to the exchange-correlation functional. Recently, the so-called strongly constrained appropriately normed (SCAN) [Sun, Ruzsinszky, and Perdew, Phys. Rev. Lett. 115, 036402 (2015)] functional has received a lot of attention due to promising results for covalent, metallic, ionic, as well as hydrogen- and van der Waals-bonded systems alike. In this work, we focus on assessing the performance of the SCAN functional for itinerant magnets by calculating basic structural and magnetic properties of the transition metals Fe, Co, and Ni. We find that although structural properties of bcc-Fe seem to be in good agreement with experiment, SCAN performs worse than standard local and semilocal functionals for fcc-Ni and hcp-Co. In all three cases, the magnetic moment is significantly overestimated by SCAN, and the 3d states are shifted to lower energies, as compared to experiments.</p>","","","","","","","","","","","","","2018-09-27","2018-09-27","2020-03-17","http://liu.diva-portal.org/smash/get/diva2:1251748/FULLTEXT01.pdf","","6","","2","urn:nbn:se:liu:diva-156835;urn:nbn:se:liu:diva-164113","","","","094413","false","","",""
"1192905","Skripnyak, Natalia [natsk33] [0000-0003-1634-5882] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ponomareva, A. V. (Natl Univ Sci and Technol MISIS, Russia);Belov, M. P. (Natl Univ Sci and Technol MISIS, Russia);Abrikosov, Igor A. [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Ab initio calculations of elastic properties of alloys with mechanical instability: Application to BCC Ti-V alloys","Artikel i tidskrift","Refereegranskat","eng","Materials & design","0264-1275","1873-4197","published","140","","","357","365","2018","","","","Elsevier","","","","","https://www.ifm.liu.se/theomod/theophys/publications/fulltexts/artikel-med-forsattsblad-(002).pdf","","10.1016/j.matdes.2017.11.071","000424943900037","","","urn:nbn:se:liu:diva-145445","","","Efficient first-principal simulations; Elastic moduli; Substitutional disorder; Ti-V alloys; Mechanical stabilization","Annan materialteknik (20599)","","","<p>Funding Agencies|Ministry of Education and Science of the Russian Federation [K2-2016-013, 211]; Swedish Research Council [2015-04391]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]</p>","<p>Considering Ti-V alloys with the body-centered cubic crystal lattice, a system with mechanical instability for Tirich alloys, we calculate their elastic properties using Projector Augmented Wave method and the exact muffin tin orbital method in a complete interval of V concentrations. The substitutional disorder is modeled using the special quasi-random structures technique and the coherent potential approximation. The efficiency and accuracy of the simulation techniques is analyzed, and a strategy for efficient high-throughput calculations of elastic properties of disordered alloys is proposed. Dependences of the single crystal elastic moduli on V concentration and a set ofmechanical characteristics of polycrystalline alloys are presented and discussed. The effect of V content on themechanical stabilization of the bcc Ti-V alloys is investigated. In agreement with experiment, we find that titanium-rich alloys are mechanically unstable, however the alloys becomemechanically stablewith increasing content of V in the system. We observe a nonlinear dependence of the alloys Youngs moduli in a vicinity of the mechanical stabilization and suggest that this effect can be used to design alloys with low values of the elastic moduli. (C) 2017 Elsevier Ltd. All rights reserved.</p>","","","","","","","","","","","","","2018-03-23","2018-03-23","2020-04-21","http://liu.diva-portal.org/smash/get/diva2:1192905/FULLTEXT01.pdf","","4","","1","urn:nbn:se:liu:diva-165270","","","","","false","true","",""
"1273233","Klarbring, Johan [johkl85] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Phase Stability of Dynamically Disordered Solids from First Principles","Artikel i tidskrift","Refereegranskat","eng","Physical Review Letters","0031-9007","1079-7114","published","121","22","","","","2018","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevLett.121.225702","000451581600011","30547633","","urn:nbn:se:liu:diva-153532","","","","Oorganisk kemi (10404)","","","<p>Funding Agencies|Swedish Research Council (VR) [2014-4750]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]</p>","<p>Theoretical studies of phase stability in solid materials with dynamic disorder are challenging due to the failure of the standard picture of atoms vibrating around fixed equilibrium positions. Dynamically disordered solid materials show immense potential in applications. In particular, superionic conductors, where the disorder results in exceptionally high ionic conductivity, are very promising as solid state electrolytes in batteries and fuel cells. The biggest obstacle in living up to this potential is the limited stability of the dynamically disordered phases. Here, we outline a method to obtain the free energy of a dynamically disordered solid. It is based on a stress-strain thermodynamic integration on a deformation path between a mechanically stable ordered variant of the disordered phase, and the dynamically disordered phase itself. We show that the large entropy contribution associated with the dynamic disorder is captured in the behavior of the stress along the deformation path. We apply the method to Bi2O3, whose superionic delta phase is the fastest known solid oxide ion conductor. We accurately reproduce the experimental transition enthalpy and the critical temperature of the phase transition from the low temperature ground state a phase to the superionic d phase. The method can be used for a first-principles description of the phase stability of superionic conductors and other materials with dynamic disorder, when the disordered phase can be connected to a stable phase through a continuous deformation path.</p>","","","","","","","","","","","","","2018-12-20","2018-12-20","2020-05-06","","","2","","2","urn:nbn:se:liu:diva-165554","","","","225702","false","","",""
"1181677","Klarbring, Johan [johkl85] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Nature of the octahedral tilting phase transitions in perovskites: A case study of CaMnO3","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","97","2","","","","2018","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.97.024108","000423118400003","","","urn:nbn:se:liu:diva-144883","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Swedish Research Council (VR) [2014-4750]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; CeNano at Linkoping University</p>","<p>The temperature-induced antiferrodistortive (AFD) structural phase transitions in CaMnO3, a typical perovskite oxide, are studied using first-principles density functional theory calculations. These transitions are caused by tilting of the MnO6 octahedra that are related to unstable phonon modes in the high-symmetry cubic perovskite phase. Transitions due to octahedral tilting in perovskites normally are believed to fit into the standard soft-mode picture of displacive phase transitions. We calculate phonon-dispersion relations and potential-energy landscapes as functions of the unstable phonon modes and argue based on the results that the phase transitions are better described as being of order-disorder type. This means that the cubic phase emerges as a dynamical average when the system hops between local minima on the potential-energy surface. We then perform ab initio molecular dynamics simulations and find explicit evidence of the order-disorder dynamics in the system. Our conclusions are expected to be valid for other perovskite oxides, and we finally suggest how to predict the nature (displacive or order-disorder) of the AFD phase transitions in any perovskite system.</p>","","","","","","","","","","","","","2018-02-09","2018-02-09","2020-05-06","http://liu.diva-portal.org/smash/get/diva2:1181677/FULLTEXT01.pdf","","2","","2","urn:nbn:se:liu:diva-165554","","","","024108","false","","",""
"1199551","Klarbring, Johan [johkl85] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Skorodumova, Natalia V. (KTH Royal Inst Technol, Sweden; Uppsala Univ, Sweden);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Finite-temperature lattice dynamics and superionic transition in ceria from first principles","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","97","10","","","","2018","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.97.104309","000427982100003","","","urn:nbn:se:liu:diva-147104","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Swedish Research Council [2014-4750, 2014-5993]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]</p>","<p>Ab initio molecular dynamics (AIMD) in combination with the temperature dependent effective potential (TDEP) method has been used to go beyond the quasiharmonic approximation and study the lattice dynamics in ceria, CeO2, at finite temperature. The results indicate that the previously proposed connection between the B-1u phonon mode turning imaginary and the transition to the superionic phase in fluorite structured materials is an artifact of the failure of the quasiharmonic approximation in describing the lattice dynamics at elevated temperatures. We instead show that, in the TDEP picture, a phonon mode coupling to the E-u mode prevents the B-1u mode from becoming imaginary. We directly observe the superionic transition at high temperatures in our AIMD simulations and find that it is initiated by the formation of oxygen Frenkel pairs (FP). These FP are found to form in a collective process involving simultaneous motion of two oxygen ions.</p>","","","","","","","","","","","","","2018-04-20","2018-04-20","2020-05-06","","","3","","2","urn:nbn:se:liu:diva-165554","","","","104309","false","","",""
"1265296","Mosyagin, Igor [igomo87] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (NUST MISIS, Russia);Gambino, Davide [davga91] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Sangiovanni, Davide [davsa82] [0000-0002-1379-6656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Ruhr Univ Bochum, Germany);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (NUST MISIS, Russia);Caffrey, Nuala M. [n/a] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Trinity Coll Dublin, Ireland)","Effect of dispersion corrections on ab initio predictions of graphite and diamond properties under pressure","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","98","17","","","","2018","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.98.174103","000449514900001","","","urn:nbn:se:liu:diva-152804","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Swedish Research Council (VR) [2015-04391, 2014-4750, 637-2013-7296]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; Russian Science Foundation [18-12-00492]; Olle Engkvist Foundation; Science Foundation Ireland Starting Investigator Research Grant [15/SIRG/3314]</p>","<p>There are several approaches to the description of van der Waals (vdW) forces within density functional theory. While they are generally found to improve the structural and energetic properties of those materials dominated by weak dispersion forces, it is not known how they behave when the material is subject to an external pressure. This could be an issue when considering the pressure-induced structural phase transitions, which are currently attracting great attention following the discovery of an ultrahard phase formed by the compression of graphite at room temperature. In order to model this transition, the functional must be capable of simultaneously describing both strong covalent bonds and weak dispersion interactions as an isotropic pressure is applied. Here, we report on the ability of several dispersion-correction functionals to describe the energetic, structural, and elastic properties of graphite and diamond, when subjected to an isotropic pressure. Almost all of the tested vdW corrections provide an improved description of both graphite and diamond compared to the local density approximation. The relative error does not change significantly as pressure is applied, and in some cases even decreases. We therefore conclude that the use of dispersion-corrected exchange-correlation functionals, which have been neglected to date, will improve the accuracy and reliability of theoretical investigations into the pressure-induced phase transition of graphite.</p>","","","","","","","","","","","","","2018-11-22","2018-11-22","2020-09-11","http://liu.diva-portal.org/smash/get/diva2:1265296/FULLTEXT01.pdf","","5","","2","","","","","174103","false","","",""
"1182425","Xia, Chao [chaxi72] (Linköpings universitet [276], Tekniska fakulteten [872902]) (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]);Tal, Alexey [aleta94] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia);Johansson, Leif [leijo19] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Olovsson, Weine [weiol14] [0000-0002-2904-0108] (Linköpings universitet [276], Tekniska fakulteten [872902]) (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Virojanadara, Chariya [chavi32] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Effects of rhenium on graphene grown on SiC(0001)","Artikel i tidskrift","Refereegranskat","eng","Journal of Electron Spectroscopy and Related Phenomena","0368-2048","1873-2526","published","222","","","117","121","2018","","","","Elsevier","","","","","","","10.1016/j.elspec.2017.07.006","000423638100016","","","urn:nbn:se:liu:diva-145152","","","Rhenium; Graphene; Photoelectron spectroscopy; Core-level shift; Ab initio density functional theory","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Knut and Alice Wallenberg Foundation [2012.0083]; Knut and Alice Wallenberg Foundation through CoTXS; Swedish Foundation or Strategic Research (SSF) program SRL Grant [10-0026]; Swedish Research Council (VR) [2015-04391]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [200900971]; Ministry of Education and Science of the Russian Federation [14.Y26.31.0005]; Swedish Research Council [621-2011-4252]</p>","<p>We study the effects of Rhenium (Re) deposited on epitaxial monolayer graphene grown on SiC(0001) and after subsequent annealing at different temperatures, by performing high resolution photoelectron spectroscopy (PES) and angle resolved photoelectron spectroscopy (ARPES). The graphene-Re system is found to be thermally stable. While no intercalation or chemical reaction of the Re is detected after deposition and subsequent annealing up to 1200 degrees C, a gradual decrease in the binding energy of the Re 4f doublet is observed. We propose that a larger mobility of the Re atoms with increasing annealing temperature and hopping of Re atoms between different defective sites on the graphene sample could induce this decrease of Re 4f binding energy. This is corroborated by first principles density functional theory (DFT) calculations of the Re core-level binding energy shift. No change in the doping or splitting of the initial monolayer graphene electronic band structure is observed after Re deposition and annealing up to 1200 degrees C, only a broadening of the bands. (C) 2017 Elsevier B.V. All rights reserved.</p>","","","","","","","","","","","","","2018-02-13","2018-02-13","2020-09-15","http://liu.diva-portal.org/smash/get/diva2:1182425/FULLTEXT02.pdf","","6","","1","","","","","","true","","",""
"1209583","Eriksson, Peter [peter35] [0000-0002-1192-1492] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Molekylär ytfysik och nanovetenskap [9601]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Tal, Alexey [aleta94] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Skallberg, Andreas [andsk54] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Molekylär ytfysik och nanovetenskap [9601]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Brommesson, Caroline [carsk36] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Molekylär ytfysik och nanovetenskap [9601]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Hu, Zhang-Jun [zhahu14] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Molekylär ytfysik och nanovetenskap [9601]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Boyd, Robert [robbo87] [0000-0002-6602-7981] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Plasma och beläggningsfysik [2225]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Olovsson, Weine [weiol14] [0000-0002-2904-0108] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Fairley, Neal (Casa Software Ltd, Bay House, Teignmouth, United Kingdom);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Materials Modeling and Development Laboratory, National University of Science and Technology “MISIS”, Moscow, Russia);Zhang, Xuanjun (Faculty of Health Sciences, University of Macau, Macau, SAR, China);Uvdal, Kajsa [kajuv09] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Molekylär ytfysik och nanovetenskap [9601]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Cerium oxide nanoparticles with antioxidant capabilities and gadolinium integration for MRI contrast enhancement","Artikel i tidskrift","Refereegranskat","eng","Scientific Reports","2045-2322","2045-2322","published","8","","","","","2018","","","","Nature Publishing Group","","","","","","","10.1038/s41598-018-25390-z","000431293100003","29725117","2-s2.0-85046679522","urn:nbn:se:liu:diva-147910","","","","Annan fysik (10399)","","","<p>Funding Agencies|Swedish Research Council [621-2013-5357]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; Knut and Alice Wallenberg Foundation [2012.0083 CTS 15:507]; Centre in Nano Science and Nano technology at LiTH (CeNano) at Linkoping University; CoTXS; Ministry of Education and Science of the Russian Federation [14.Y26.31.0005, K2-2017-080, 211]</p>","<p>The chelating gadolinium-complex is routinely used as magnetic resonance imaging (MRI) -contrast enhancer. However, several safety issues have recently been reported by FDA and PRAC. There is an urgent need for the next generation of safer MRI-contrast enhancers, with improved local contrast and targeting capabilities. Cerium oxide nanoparticles (CeNPs) are designed with fractions of up to 50% gadolinium to utilize the superior MRI-contrast properties of gadolinium. CeNPs are well-tolerated in vivo and have redox properties making them suitable for biomedical applications, for example scavenging purposes on the tissue-and cellular level and during tumor treatment to reduce in vivo inflammatory processes. Our near edge X-ray absorption fine structure (NEXAFS) studies show that implementation of gadolinium changes the initial co-existence of oxidation states Ce3+ and Ce4+ of cerium, thereby affecting the scavenging properties of the nanoparticles. Based on ab initio electronic structure calculations, we describe the most prominent spectral features for the respective oxidation states. The as-prepared gadolinium-implemented CeNPs are 3-5 nm in size, have r(1)-relaxivities between 7-13 mM(-1) s(-1) and show clear antioxidative properties, all of which means they are promising theranostic agents for use in future biomedical applications.</p>","","","","","","","","","","","","","2018-05-23","2018-05-23","2020-10-16","http://liu.diva-portal.org/smash/get/diva2:1209583/FULLTEXT01.pdf","","11","","1","urn:nbn:se:liu:diva-159949;urn:nbn:se:liu:diva-170598","","","","6999","true","true","",""
"1267324","Bykova, E. (DESY, Germany; Univ Bayreuth, Germany);Bykov, M. (Univ Bayreuth, Germany; Natl Univ Sci and Technol MISIS, Russia);Cernok, A. (Univ Bayreuth, Germany; Open Univ, England);Tidholm, Johan [johti34] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Hellman, Olle [olohe96] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (CALTECH, CA 91125 USA);Belov, M. P. (Natl Univ Sci and Technol MISIS, Russia);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Liermann, H. -P. (DESY, Germany);Hanfland, M. (European Synchrotron Radiat Facil, France);Prakapenka, V. B. (Univ Chicago, IL 60637 USA);Prescher, C. (Univ Chicago, IL 60637 USA; Univ Cologne, Germany);Dubrovinskaia, N. (Univ Bayreuth, Germany);Dubrovinsky, L. (Univ Bayreuth, Germany)","Metastable silica high pressure polymorphs as structural proxies of deep Earth silicate melts","Artikel i tidskrift","Refereegranskat","eng","Nature Communications","2041-1723","2041-1723","published","9","","","","","2018","","","","NATURE PUBLISHING GROUP","","","","","","","10.1038/s41467-018-07265-z","000450160100002","30442940","","urn:nbn:se:liu:diva-153165","","","","Materialkemi (10403)","","","<p>Funding Agencies|German Research Foundation [Deutsche Forschungsgemeinschaft (DFG)]; Federal Ministry of Education and Research [ Bundesministerium fur Bildung und Forschung (BMBF), Germany] [DU 954-11/1, DU 393-9/2, DU 393-10/1, 5K16WC1]; National Science Foundation-Earth Sciences [EAR-1634415]; Department of Energy-GeoSciences [DE-FG02-94ER14466]; DOE Office of Science by Argonne National Laboratory [DE-AC02-06CH11357]; Elite Network of Bavaria through the program Oxides; Swedish Research Council [2015-04391, 2014-4750, 637-2013-7296]; Swedish Government Strategic Research Areas in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [200900971]; Swedish e-Science Research Centre (SeRC); Ministry of Education and Science of the Russian Federation [14.Y26.31.0005]; Ministry of Education and Science of the Russian Federation in the framework of Increase Competitiveness Program of NUST ""MISIS"" [K2-2017-080]</p>","<p>Modelling of processes involving deep Earth liquids requires information on their structures and compression mechanisms. However, knowledge of the local structures of silicates and silica (SiO2) melts at deep mantle conditions and of their densification mechanisms is still limited. Here we report the synthesis and characterization of metastable high-pressure silica phases, coesite-IV and coesite-V, using in situ single-crystal X-ray diffraction and ab initio simulations. Their crystal structures are drastically different from any previously considered models, but explain well features of pair-distribution functions of highly densified silica glass and molten basalt at high pressure. Built of four, five-, and six-coordinated silicon, coesite-IV and coesite-V contain SiO6 octahedra, which, at odds with 3rd Paulings rule, are connected through common faces. Our results suggest that possible silicate liquids in Earths lower mantle may have complex structures making them more compressible than previously supposed.</p>","","","","","","","","","","","","","2018-12-01","2018-12-01","2020-10-22","http://liu.diva-portal.org/smash/get/diva2:1267324/FULLTEXT01.pdf","","14","","2","urn:nbn:se:liu:diva-170800","","","","4789","false","","",""
"1236453","Bykov, Maxim (Univ Bayreuth, Germany);Bykova, Elena (Deutsch Elektronen Synchrotron DESY, Germany);Koemets, Egor (Univ Bayreuth, Germany);Fedotenko, Timofey (Univ Bayreuth, Germany);Aprilis, Georgios (Univ Bayreuth, Germany);Glazyrin, Konstantin (Deutsch Elektronen Synchrotron DESY, Germany);Liermann, Hanns-Peter (Deutsch Elektronen Synchrotron DESY, Germany);Ponomareva, Alena V. (Natl Univ Sci and Technol MISIS, Russia);Tidholm, Johan [johti34] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Tasnadi, Ferenc [ferta55] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abrikosov, Igor A. [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Dubrovinskaia, Natalia (Univ Bayreuth, Germany);Dubrovinsky, Leonid (Univ Bayreuth, Germany)","High-Pressure Synthesis of a Nitrogen-Rich Inclusion Compound ReN<sub>8</sub>·xN<sub>2</sub> with Conjugated Polymeric Nitrogen Chains","Artikel i tidskrift","Refereegranskat","eng","Angewandte Chemie International Edition","1433-7851","1521-3773","published","57","29","","9048","9053","2018","","","","WILEY-V C H VERLAG GMBH","","","","","","","10.1002/anie.201805152","000438195200045","29774981","","urn:nbn:se:liu:diva-149844","","","high-energy-density materials; high-pressure chemistry; nitrides; polymeric nitrogen; X-ray diffraction","Oorganisk kemi (10404)","","","<p>Funding Agencies|German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) [DU 954-8/1, DU 954-11/1]; Federal Ministry of Education and Research, Germany (BMBF) [5K16WC1]; DFG [FOR2125, FOR 2440]; Ministry of Education and Science of the Russian Federation [14.Y26.31.0005, K2-2017-080]; Swedish Research Council (VR) [2015-04391]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; VINN Excellence Center Functional Nanoscale Materials (FunMat-2) Grant [2016-05156]</p>","<p>A nitrogen-rich compound, ReN(8)xN(2), was synthesized by a direct reaction between rhenium and nitrogen at high pressure and high temperature in a laser-heated diamond anvil cell. Single-crystal X-ray diffraction revealed that the crystal structure, which is based on the ReN8 framework, has rectangular-shaped channels that accommodate nitrogen molecules. Thus, despite a very high synthesis pressure, exceeding 100GPa, ReN(8)xN(2) is an inclusion compound. The amount of trapped nitrogen (x) depends on the synthesis conditions. The polydiazenediyl chains [-N=N-] that constitute the framework have not been previously observed in any compound. Abinitio calculations on ReN(8)xN(2) provide strong support for the experimental results and conclusions.</p>","","","","","","","","","","","","","2018-08-02","2018-08-02","2020-10-22","http://liu.diva-portal.org/smash/get/diva2:1236453/FULLTEXT01.pdf","","13","","2","urn:nbn:se:liu:diva-170800","","","","","false","","",""
"1254061","Fallqvist, Amie [amifa57] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Olovsson, Weine [weiol14] [0000-0002-2904-0108] (Linköpings universitet [276], Tekniska fakulteten [872902]) (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Max Planck Inst Eisenforsch GmbH, Germany);Palisaitis, Justinas [juspa01] [0000-0003-3203-7935] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Belov, M. P. (Natl Univ Sci and Technol MISIS, Russia);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Hultman, Lars [larhu75] [0000-0002-2837-3656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Persson, Per O A [perpe25] [0000-0001-9140-6724] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Resolving the debated atomic structure of the metastable cubic SiNx tissue phase in nanocomposites with TiN","Artikel i tidskrift","Refereegranskat","eng","Physical Review Materials","","2475-9953","published","2","9","","","","2018","","","","American Physical Society","","","","","","","10.1103/PhysRevMaterials.2.093608","000445181600001","","","urn:nbn:se:liu:diva-151780","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Swedish Research Council (VR) [2008-405, 2012-4359, 2015-04391, 2016-04412]; Swedish Foundation for Strategic Research (SSF) through FunCase; SRL [10-0026]; M. Bergwall foundation; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; Ministry of Education and Science of the Russian Federation [14.Y26.31.0005, K2-2017-080]; [RIF 14-0074]</p>","<p>The TiN/SiNx nanocomposite and nanolaminate systems are the archetype for super if not ultrahard materials. Yet, the nature of the SiNx tissue phase is debated. Here, we show by atomically resolved electron microscopy methods that SiNx is epitaxially stabilized in a NaCl structure on the adjacent TiN(001) surfaces. Additionally, electron energy loss spectroscopy, supported by first-principles density functional theory calculations infer that SiNx hosts Si vacancies.</p>","","","","","","","","","","","","","2018-10-08","2018-10-08","2020-12-15","http://liu.diva-portal.org/smash/get/diva2:1254061/FULLTEXT01.pdf","","8","","1","","","","","093608","true","","",""
"1262092","Ektarawong, Annop [annek02] [0000-0002-6059-6833] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Max Planck Inst Eisenforsch GmbH, Germany)","Effect of temperature and configurational disorder on the electronic band gap of boron carbide from first principles","Artikel i tidskrift","Refereegranskat","eng","Physical Review Materials","","2475-9953","published","2","10","","","","2018","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevMaterials.2.104603","000447735500002","","","urn:nbn:se:liu:diva-152617","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Swedish Research Council (VR) [2014-6336, 2014-4750]; Marie Sklodowska Curie Actions, Cofund [INCA 600398]; Swedish Foundation for Strategic Research (SSF) through the Future Research Leaders 6 program; Kungl. Ingenjorsvetenskapsakademiens Hans Werthen-Fond; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]</p>","<p>The overestimation, rather than the usual underestimation, of the electronic band gap at 0 K of boron carbide with the ideally stoichiometric composition of B4C, represented by B11CP (CBC), in density functional theory calculations is one of the outstanding controversial issues in the field of icosahedral boron-rich solids. Using a first-principles approach, we explore the effect of temperature and configurational disorder on the electronic band gap of B4C. Ab initio molecular dynamics simulations are performed to account for the effects of vibrational disorder. The results reveal that the volumetric thermal expansion as well as the thermally induced configurational disorder of icosahedral C-P atoms residing in the B11CP icosahedra have a minimal impact on the band gap of B4C, while a major decrease of the band gap is caused by explicit atomic displacements, induced by lattice vibrations. At 298 K, the band gap of B4C is overestimated, as compared to the experimental value, by approximately 31%. However, configurational disorder induced by introducing a small fraction of B-12 (CBC) and B-12 (B-4) into a matrix of B11CP (CBC) to make the composition of boron carbide approximately B4.3C, claimed to be the carbon-rich limit of the material in experiment, leads to a smaller band gap due to the appearance of midgap states. These results can explain at least a part of the previous discrepancies between theory and experiments for the band gap of boron carbide.</p>","","","","","","","","","","","","","2018-11-09","2018-11-09","2020-12-15","http://liu.diva-portal.org/smash/get/diva2:1262092/FULLTEXT01.pdf","","3","","1","","","","","104603","false","","",""
"1192479","Davidsson, Joel [joeda01] [0000-0002-5349-3318] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ivády, Viktor [vikiv58] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Hungarian Acad Sci, Hungary);Armiento, Rickard [ricar47] [0000-0002-5571-0814] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Nguyen, Son Tien [nguso90] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Gali, Adam (Hungarian Acad Sci, Hungary; Budapest Univ Technol and Econ, Hungary);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Natl Univ Sci and Technol MISIS, Russia)","First principles predictions of magneto-optical data for semiconductor point defect identification: the case of divacancy defects in 4H-SiC","Artikel i tidskrift","Refereegranskat","eng","New Journal of Physics","1367-2630","1367-2630","published","20","","","","","2018","","","","IOP PUBLISHING LTD","","","","","","","10.1088/1367-2630/aaa752","000425349000003","","","urn:nbn:se:liu:diva-145768","","","point defects; zero-phonon line; hyperfine field; DFT; convergence; SiC","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Swedish Government Strategic Research Areas in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; Swedish e-Science Centre (SeRC); Centre in Nano science and Nanotechnology (CeNano); Knut&Alice Wallenberg Foundation New States of Matter (COTXS); Swedish Research Council (VR) [2015-04391, 2016-04810, 2016-04068]; Linkoping University [LiU-2015-00017-60]; Swedish National Infrastructure for Computing Grants [SNIC 001/12-275, SNIC 2013/1-331, SNIC 2016/1-528]; Ministry of Education and Science of the Russian Federation [14.Y26.31.0005, K2-2017-080]; US Department of Energy, Office of Science, Office of Basic Energy Sciences [DE-AC02-06CH11357]; National Research Development and Innovation Office of Hungary within the Quantum Technology National Excellence Program [2017-1.2.1-NKP-2017-00001]</p>","<p>Study and design of magneto-optically active single point defects in semiconductors are rapidly growing fields due to their potential in quantum bit (qubit) and single photon emitter applications. Detailed understanding of the properties of candidate defects is essential for these applications, and requires the identification of the defects microscopic configuration and electronic structure. In multicomponent semiconductors point defects often exhibit several non-equivalent configurations of similar but different characteristics. The most relevant example of such point defect is the divacancy in silicon carbide, where some of the non-equivalent configurations implement room temperature qubits. Here, we identify four different configurations of the divacancy in 4H-SiC via the comparison of experimental measurements and results of first-principle calculations. In order to accomplish this challenging task, we carry out an exhaustive numerical accuracy investigation of zero-phonon line and hyperfine coupling parameter calculations. Based on these results, we discuss the possibility of systematic quantum bit search.</p>","","","","","","","","","","","","","2018-03-22","2018-03-22","2021-02-08","http://liu.diva-portal.org/smash/get/diva2:1192479/FULLTEXT01.pdf","","6","","1","urn:nbn:se:liu:diva-173108","","","","023035","false","","",""
"1068924","Tasnadi, Ferenc [ferta55] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Lugovskoy, Andrey V. (NUST MISIS, Russia);Odén, Magnus [magod41] [0000-0002-2286-5588] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Nanostrukturerade material [2221]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (NUST MISIS, Russia)","Non-equilibrium vacancy formation energies in metastable alloys - A case study of Ti0.5Al0.5N","Artikel i tidskrift","Refereegranskat","eng","MATERIALS and DESIGN","0264-1275","","published","114","","","484","493","2017","","","","ELSEVIER SCI LTD","","","","","","","10.1016/j.matdes.2016.10.071","000390650800058","","","urn:nbn:se:liu:diva-134066","","","Metastable materials; Non-equilibrium; Vacancy formation energy; Hard coatings; Supercell approach","Metallurgi och metalliska material (20506)","","","<p>Funding Agencies|Swedish Foundation for Strategic Research (SSF) project Designed Multicomponent coatings (MultiFilms); SRL Grant [10-0026]; M-ERA.NET Multiscale Computational-design of novel hard nanostructure Coatings (MC2) project; Swedish Research Council (VR) [2015-04391]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; Ministry of Education and Science of the Russian Federation [14.Y26.31.0005]</p>","<p>In this study, we present a computational technique to investigate non-equilibrium vacancies in metastable alloys. In contrast to equilibrium materials, calculation of the energy of removing an alloying atom requires a finite size configurational correction. We explain that in metastable alloys the vacancy formation energy is defined up to an arbitrary constant. We argue that in non-equilibrium alloys no statistical considerations are required and there is a distribution of the vacancy formation energy with large variation. We show for the example of Ti0.5Al0.5N that the configuration correction is significant. Using cluster expansion, we demonstrate the major importance of the first two metallic coordination shells in Ti0.5Al0.5N. We introduce a three-dimensional representation of the energies of removing Ti and Al atoms as a function of number of Al atoms in the neighboring shells and we predict the metal atom vacancy formation energy in arbitrary local chemical environments. Neglecting the interactions between the vacant sites and assuming their simultaneous occurrence, we show how to extract information about the energy cost of a vacancy concentration in metastable alloys. We conclude that in metastable disordered alloys vacancies should occur in local environments that correspond to the lowest formation energies rather than distributed statistically. (C) 2016 Elsevier Ltd. All rights reserved.</p>","","","","","","","","","","","","","2017-01-22","2017-01-26","2017-01-26","","","4","","0","","","","","","false","","",""
"1071711","Mukhamedov, B. O. (National University of Science and Technology MISIS, Russia);Ponomareva, A. V. (National University of Science and Technology MISIS, Russia);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Spinodal decomposition in ternary Fe-Cr-Co system","Artikel i tidskrift","Refereegranskat","eng","JOURNAL OF ALLOYS AND COMPOUNDS","0925-8388","","published","695","","","250","256","2017","","","","ELSEVIER SCIENCE SA","","","","","","","10.1016/j.jallcom.2016.10.185","000391817600031","","","urn:nbn:se:liu:diva-134299","","","First-principles simulations; Spinodal decomposition; Fe-Cr-Co alloys","Metallurgi och metalliska material (20506)","","","<p>Funding Agencies|Ministry of Education and Science of the Russian Federation [RFMEFI58715X0023]; Swedish Foundation for Strategic Research (SSF) program SRL [10-0026]</p>","<p>Using the exact muffin-tin orbitals method in conjunction with the coherent potential approximation we have studied the tendency towards spinodal decomposition of solid solution in ternary Fe-Cr-Co system. In addition, we have estimated the Curie temperature of the alloys, and considered the influence of the magnetic state on the decomposition thermodynamics of the ternary alloys. Using the mean field approximation, we have estimated the finite temperature effects on the alloys free energy. We predict that an increase Co and Cr content in the ternary Fe-Cr-Co system increases the tendency of the bcc (alpha)-FexCryCoz alloys towards the spinodal decomposition. Because of this, high magnetic properties and high thermal stability of these properties can be expected in the Fe-Cr-Co alloys with high Co content. (C) 2016 Elsevier B.V. All rights reserved.</p>","","","","","","","","","","","","","2017-02-03","2017-02-06","2017-02-06","","","3","","0","","","","","","false","","",""
"1071706","Shulumba, Nina (CALTECH, CA 91125 USA);Hellman, Olle [olohe96] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (CALTECH, CA 91125 USA);Minnich, Austin J. (CALTECH, CA 91125 USA)","Intrinsic localized mode and low thermal conductivity of PbSe","Artikel i tidskrift","Refereegranskat","eng","PHYSICAL REVIEW B","2469-9950","","published","95","1","","","","2017","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.95.014302","000391305600003","","","urn:nbn:se:liu:diva-134301","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|DARPA MATRIX program [HR0011-15-2-0039]; Swedish Research Council (VR) program [637-2013-7296]; National Science Foundation [ACI-1053575]; Swedish National Infrastructure for Computing (SNIC) at PDC Center (High Performance Computing at the KTH Royal Institute of Technology); National Supercomputer Centre (NSC) at Linkoping University</p>","<p>Lead chalcogenides such as PbS, PbSe, and PbTe are of interest for their exceptional thermoelectric properties and strongly anharmonic lattice dynamics. Although PbTe has received the most attention, PbSe has a lower thermal conductivity and a nonlinear temperature dependence of thermal resistivity despite being stiffer, trends that prior first-principles calculations have not fully reproduced. Here, we use ab initio calculations that explicitly account for strong anharmonicity and a computationally efficient stochastic phase-space sampling scheme to identify the origin of this low thermal conductivity as an anomalously large anharmonic interaction, exceeding in strength that in PbTe, between the transverse optic and longitudinal acoustic branches. The strong anharmonicity is reflected in the striking observation of an intrinsic localized mode that forms in the acoustic frequencies. Our work shows the deep insights into thermal phonons that can be obtained from ab initio calculations that do not rely on perturbations from the ground-state phonon dispersion.</p>","","","","","","","","","","","","","2017-02-03","2017-02-06","2017-02-22","http://liu.diva-portal.org/smash/get/diva2:1071706/FULLTEXT01.pdf","","3","","0","","","","","014302","false","","",""
"1089993","Brodin, G. (Umeå University, Sweden);Stenflo, Lennart [lenst65] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","A simple electron plasma wave","Artikel i tidskrift","Refereegranskat","eng","Physics Letters A","0375-9601","1873-2429","published","381","11","","1033","1035","2017","","","","ELSEVIER SCIENCE BV","","","","","","","10.1016/j.physleta.2016.11.034","000395230300015","","","urn:nbn:se:liu:diva-136586","","","Large amplitude waves; Plasma oscillations; Parametric processes","Fusion, plasma och rymdfysik (10303)","","","","<p>Considering a class of solutions where the density perturbations are functions of time, but not of space, we derive a new exact large amplitude wave solution for a cold uniform electron plasma. This result illustrates that most simple analytical solutions can appear even if the density perturbations are large. (C) 2016 Elsevier B.V. All rights reserved.</p>","","","","","","","","","","","","","2017-04-21","2017-04-21","2017-04-21","","","2","","1","","","","","","false","","",""
"1090306","Belonoshko, Anatoly B. (Royal Institute Technology KTH, Sweden);Lukinov, Timofei (Royal Institute Technology KTH, Sweden);Fu, Jie (Royal Institute Technology KTH, Sweden; Dalian University of Technology, Peoples R China);Zhao, Jijun (Dalian University of Technology, Peoples R China);Davis, Sergio (Chilean Comm Nucl Energy CCHEN, Chile);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Stabilization of body-centred cubic iron under inner-core conditions","Artikel i tidskrift","Refereegranskat","eng","Nature Geoscience","1752-0894","1752-0908","published","10","4","","312","+","2017","","","","NATURE PUBLISHING GROUP","","","","","","","10.1038/NGEO2892","000398162800021","","","urn:nbn:se:liu:diva-136573","","","","Geokemi (10506)","","","<p>Funding Agencies|Swedish Research Council (VR) [2013-5767, 2014-4750]; National Magnetic Confinement Fusion Program of China [2015GB118000]; China Scholarship Council; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]</p>","<p>The Earths solid core is mostly composed of iron. However, despite being central to our understanding of core properties, the stable phase of iron under inner-core conditions remains uncertain. The two leading candidates are hexagonal close-packed and body-centred cubic (bcc) crystal structures, but the dynamic and thermodynamic stability of bcc iron under inner-core conditions has been challenged. Here we demonstrate the stability of the bcc phase of iron under conditions consistent with the centre of the core using ab initio molecular dynamics simulations. We find that the bcc phase is stabilized at high temperatures by a diffusion mechanism that arises due to the dynamical instability of the phase at lower temperatures. On the basis of our simulations, we reinterpret experimental data as support for the stability of bcc iron under inner-core conditions. We suggest that the diffusion of iron atoms in solid state may explain both the anisotropy and the low shear modulus of the inner core.</p>","","","","","","","","","","","","","2017-04-24","2017-04-24","2017-05-21","","","6","","2","","","","","","false","","",""
"1097355","Cirera, B. (IMDEA Nanosci, Spain);Björk, Jonas [jonbj66] [0000-0002-1345-0006] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Otero, R. (IMDEA Nanosci, Spain; University of Autonoma Madrid, Spain);Gallego, J. M. (CSIC, Spain);Miranda, R. (IMDEA Nanosci, Spain; University of Autonoma Madrid, Spain);Ecija, D. (IMDEA Nanosci, Spain)","Efficient Lanthanide Catalyzed Debromination and Oligomeric Length-Controlled Ullmann Coupling of Aryl Halides","Artikel i tidskrift","Refereegranskat","eng","The Journal of Physical Chemistry C","1932-7447","1932-7455","published","121","14","","8033","8041","2017","","","","AMER CHEMICAL SOC","","","","","","","10.1021/acs.jpcc.7b02172","000399629000049","","","urn:nbn:se:liu:diva-137611","","","","Organisk kemi (10405)","","","<p>Funding Agencies|EC FP7-PEOPLE-COFUND AMAROUT II program; Spanish Ramon and Cajal Program [RYC-2012-11133]; Spanish Ministerio de Economia y Competitividad [FIS 2013-40667-P, FIS 2015-67287-P]; Comunidad de Madrid (projects MAD2D, NANOFRONTMAG) [52013/MT-2850]; IMDEA Foundation</p>","<p>Lanthanide elements play a vital role in a broad range of high-tech applications, and there is an increasing interest in their catalytic activity, particularly in organo-metallics. However, their catalytic role on surfaces remains unexplored. Here, we present a scanning tunneling microscopy and density functional theory study of the debromination, contacting, and coupling of dibromine terphenyl species with Dy (f-block element) and Ag (d-block element) adatoms, respectively. We show that Dy debrominates the targeted species more efficiently than Ag adatoms at room temperature, promoting the formation of unprecedented C-Dy-C organo-metallic supramolecules versus C-Ag-C parallel chains for the Ag case. DFT calculations corroborate our results showing an almost spontaneous debromination process with Dy compared to Ag. Upon annealing, for samples containing Dy, the formation of C-Ag-C organometallic bonds and concomitant C-C coupling is inhibited, giving rise to a self-assembly of debrominated monomers, showing only a minority number of covalent dimes species. For samples without Dy covalent chains of irregular length are promoted. Our studies open new avenues for using lanthanide elements as efficient dehalogenation catalysts. Furthermore, we illustrate their potential as inhibitors of uncontrolled C-C coupling reactions, of great relevance for fine-tuning the length of polymeric compounds.</p>","","","","","","","","","","","","","2017-05-22","2017-05-22","2017-05-22","","","6","","1","","","","","","false","","",""
"1098089","Leonov, I. (University of Augsburg, Germany; National University of Science and Technology MISIS, Russia);Greenberg, E. (Tel Aviv University, Israel; University of Chicago, IL USA);Belov, M. P. (National University of Science and Technology MISIS, Russia);Rozenberg, G. Kh. (Tel Aviv University, Israel);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Mott transition and magnetic collapse in iron-bearing compounds under high pressure","Artikel i tidskrift","Refereegranskat","eng","High Pressure Research","0895-7959","1477-2299","published","37","2","","96","118","2017","","","","TAYLOR & FRANCIS LTD","","","","","","","10.1080/08957959.2017.1302445","000399885500002","","","urn:nbn:se:liu:diva-137587","","","Strong correlations; high pressure; Mott metal-insulator transition; spin-state transition; transition metal oxides","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Deutsche Forschungsgemeinschaft through Transregio TRR [80]; Ministry of Education and Science of the Russian Federation [K3-2016-027, 14.Y26.31.0005]; Russian Foundation for Basic Research [16-02-01027]; Swedish Research Council (VR) [2015-04391]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; Israel Science Foundation [1189/14]</p>","<p>We discuss the electronic, magnetic, and related structural transitions in the iron-based Mott insulators under high pressures relevant to the Earths lower mantle conditions. The paper focuses on the above-mentioned topics based primarily on our theoretical analysis and various experimental studies employing synchrotron X-ray diffraction, Fe-57 Mossbauer spectroscopy, and electrical transport measurements. We review the main theoretical tools employed for the analysis of the properties of materials with strongly interacting electrons and discuss the problems of theoretical description of such systems. In particular, we discuss a state-of-the-art method for calculating the electronic structure of strongly correlated materials, the DFT + DMFT method, which merges standard band-structure techniques (DFT) with dynamical mean-field theory of correlated electrons (DMFT). We employ this method to study the pressure-induced magnetic collapse in Mott insulators, such as wustite (FeO), magnesiowustite (Fe1-xMgx)O (x=0.25 and 0.75) and goethite (FeOOH), and explore the consequences of the magnetic collapse for the electronic structure and phase stability of these materials. We show that the paramagnetic cubic B1-structured FeO and (Fe,Mg)O and distorted orthorhombic (Pnma) FeOOH exhibit upon compression a high-to low-spin (HS-LS) transition, which is accompanied by a simultaneous collapse of local moments. However, the HS-LS transition is found to have different consequences for the electronic properties of these compounds. For FeO and (Fe0.75Mg0.25)O, the transition is found to be accompanied by a Mott insulator-to-metal phase transition. In contrast to that, both (Fe0.25Mg0.75)O and FeOOH remain insulating up to the highest studied pressures, indicating that a Mott insulator to band insulator phase transition takes place. Our combined theoretical and experimental studies indicate a crossover between localized to itinerant moment behavior to accompany magnetic collapse of Fe ions.</p>","","","","","","","","","","","","","2017-05-23","2017-05-23","2017-06-14","","","5","","1","","","","","","false","","",""
"1097353","Tellander, Felix (Lund University, Sweden);Berggren, Karl-Fredrik [karbe79] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Spectra, current flow, and wave-function morphology in a model PT-symmetric quantum dot with external interactions","Artikel i tidskrift","Refereegranskat","eng","PHYSICAL REVIEW A","2469-9926","","published","95","4","","","","2017","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevA.95.042115","000399932100001","","","urn:nbn:se:liu:diva-137612","","","","Annan fysik (10399)","","","","<p>In this paper we use numerical simulations to study a two-dimensional (2D) quantum dot (cavity) with two leads for passing currents (electrons, photons, etc.) through the system. By introducing an imaginary potential in each lead the system is made symmetric under parity-time inversion (PT symmetric). This system is experimentally realizable in the form of, e.g., quantum dots in low-dimensional semiconductors, optical and electromagnetic cavities, and other classical wave analogs. The computational model introduced here for studying spectra, exceptional points (EPs), wave-function symmetries and morphology, and current flow includes thousands of interacting states. This supplements previous analytic studies of few interacting states by providing more detail and higher resolution. The Hamiltonian describing the system is non-Hermitian; thus, the eigenvalues are, in general, complex. The structure of the wave functions and probability current densities are studied in detail at and in between EPs. The statistics for EPs is evaluated, and reasons for a gradual dynamical crossover are identified.</p>","","","","","","","","","","","","","2017-05-22","2017-05-22","2017-06-15","http://liu.diva-portal.org/smash/get/diva2:1097353/FULLTEXT02.pdf","","2","","0","","","","","042115","false","","",""
"1111759","Nilsson, Johan O. (KTH Royal Institute Technology, Sweden);Leetmaa, Mikael (KTH Royal Institute Technology, Sweden);Vekilova, Olga Yu (KTH Royal Institute Technology, Sweden; Uppsala University, Sweden);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Skorodumova, Natalia V. (KTH Royal Institute Technology, Sweden; Uppsala University, Sweden)","Oxygen diffusion in ceria doped with rare-earth elements","Artikel i tidskrift","Refereegranskat","eng","Physical Chemistry, Chemical Physics - PCCP","1463-9076","1463-9084","published","21","","","13723","13730","2017","","","","ROYAL SOC CHEMISTRY","","","","","","","10.1039/c6cp06460d","000402488300037","28497151","","urn:nbn:se:liu:diva-138469","","","","Teoretisk kemi (10407)","","","<p>Funding Agencies|Swedish Energy Agency (STEM) [35515-1]; Carl Tryggers Foundation [CTS 14: 433]; Swedish Research Council (VR) [2014-5993, 2014-4750]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; [LM2015070]</p>","<p>We examine the effects of the dopant type and the dopant distribution on the ion diffusion in ceria doped with rare-earth elements (Pr, Nd, Pm, Sm, Eu, and Gd). Diffusion is simulated by means of a Kinetic Monte Carlo method using input transition rates derived from diffusion barriers calculated in the framework of density functional theory (DFT). Based on diffusion simulations, we discuss the characteristics of the dopants in terms of the diffusion barriers, and study oxygen ion trajectories for different dopants and distributions. Our simulations show a trend of increasing ion diffusivity with increasing atomic number for all distributions.</p>","","","","","","","","","","","","","2017-06-19","2017-06-19","2017-06-19","","","5","","2","","","","","","false","","",""
"1120974","Shtepliuk, Ivan [ivash69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (NASU, Ukraine);Caffrey, Nuala M. (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Trinity Coll Dublin, Ireland; Trinity Coll Dublin, Ireland);Iakimov, Tihomir [tihia09] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Khranovskyy, Volodymyr [volkh14] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (National University of Science and Technology MISIS, Russia);Yakimova, Rositsa [rosia15] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902])","On the interaction of toxic Heavy Metals (Cd, Hg, Pb) with graphene quantum dots and infinite graphene","Artikel i tidskrift","Refereegranskat","eng","Scientific Reports","2045-2322","2045-2322","published","7","","","","","2017","","","","NATURE PUBLISHING GROUP","","","","","","","10.1038/s41598-017-04339-8","000403840000006","28638144","","urn:nbn:se:liu:diva-139281","","","","Atom- och molekylfysik och optik (10302)","","","<p>Funding Agencies|European Union [696656]; Swedish Research Council (VR) [621-2014-5805]; Angpanneforeningens Forskningsstiftelse [16-541]; Science Foundation Ireland (SFI) under its Starter Investigator Research Grant (SIRG) Programme [15/SIRG/3314]; Swedish Research Council (VR) Marie Sklodowska Curie International Career Grant [2015-00679]; AForsk [14-517]; Swedish Government Strategic Research Areas in Materials Science on Functional Materials at Linkoping University [2009-00971]; Knut and Alice Wallenberg Foundation through the Strong Field Physics and New States of Matter Grant; Ministry of Education and Science of the Russian Federation [14.Y26.31.0005]</p>","<p>The promise of graphene and its derivatives as next generation sensors for real-time detection of toxic heavy metals (HM) requires a clear understanding of behavior of these metals on the graphene surface and response of the graphene to adsorption events. Our calculations herein were focused on the investigation of the interaction between three HMs, namely Cd, Hg and Pb, with graphene quantum dots (GQDs). We determine binding energies and heights of both neutral and charged HM ions on these GQDs. The results show that the adsorption energy of donor-like physisorbed neutral Pb atoms is larger than that of either Cd or Hg. In contrast to the donor-like behavior of elemental HMs, the chemisorbed charged HM species act as typical acceptors. The energy barriers to migration of the neutral adatoms on GQDs are also estimated. In addition, we show how the substitution of a carbon atom by a HM adatom changes the geometric structure of GQDs and hence their electronic and vibrational properties. UV-visible absorption spectra of HM-adsorbed GQDs vary with the size and shape of the GQD. Based on our results, we suggest a route towards the development of a graphene-based sensing platform for the optical detection of toxic HMs.</p>","","","","","","","","","","","","","2017-07-07","2017-07-07","2017-08-27","http://liu.diva-portal.org/smash/get/diva2:1120974/FULLTEXT01.pdf","","6","","1","","","","","3934","false","","",""
"1151715","Mosyagin, Igor [igomo87] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (NUST MISIS, Russia);Lugovskoy, A. V. (NUST MISIS, Russia);Krasilnikov, O. M. (NUST MISIS, Russia);Vekilov, Yu. Kh. (NUST MISIS, Russia; NUST MISIS, Russia);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Ab initio calculations of pressure-dependence of high-order elastic constants using finite deformations approach","Artikel i tidskrift","Refereegranskat","eng","Computer Physics Communications","0010-4655","1879-2944","published","220","","","20","30","2017","","","","ELSEVIER SCIENCE BV","","","","","","","10.1016/j.cpc.2017.06.008","000412252300002","","","urn:nbn:se:liu:diva-142141","","","Ab initio calculations; Elastic moduli; Pressure effects in solids and liquids","Beräkningsmatematik (10105)","","","<p>Funding Agencies|Swedish Foundation for Strategic Research (SSF) program SRL Grant [10-0026]; Swedish Research Council [2015-04391, 2014-4750]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [SFO-Mat-LiU No 2009 00971]; Ministry of Education and Science of the Russian Federation [K2-2016-013, 211]</p>","<p>We present a description of a technique for ab initio calculations of the pressure dependence of second and third-order elastic constants. The technique is based on an evaluation of the corresponding Lagrangian stress tensor derivative of the total energy assuming finite size of the deformations. Important details and parameters of the calculations are highlighted. Considering body-centered cubic Mo as a model system, we demonstrate that the technique is highly customizable and can be used to investigate non-linear elastic properties under high-pressure conditions. (C) 2017 Elsevier B.V. All rights reserved.</p>","","","","","","","","","","","","","2017-10-24","2017-10-24","2017-10-24","","","6","","1","","","","","","false","","",""
"1153679","Cirera, Borja (IMDEA Nanosci, Spain);Trukhina, Olga (University of Autonoma Madrid, Spain);Björk, Jonas [jonbj66] [0000-0002-1345-0006] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Bottari, Giovanni (IMDEA Nanosci, Spain; University of Autonoma Madrid, Spain; University of Autonoma Madrid, Spain);Rodriguez-Fernandez, Jonathan (University of Autonoma Madrid, Spain);Martin-Jimenez, Alberto (IMDEA Nanosci, Spain);Islyaikin, Mikhail K. (Ivanovo State University of Chemistry and Technology, Russia);Otero, Roberto (IMDEA Nanosci, Spain; University of Autonoma Madrid, Spain);Gallego, Jose M. (CSIC, Spain);Miranda, Rodolfo (IMDEA Nanosci, Spain; University of Autonoma Madrid, Spain);Torres, Tomas (IMDEA Nanosci, Spain; University of Autonoma Madrid, Spain; University of Autonoma Madrid, Spain);Ecija, David (IMDEA Nanosci, Spain)","Long-Range Orientational Self-Assembly, Spatially Controlled Deprotonation, and Off-Centered Metalation of an Expanded Porphyrin","Artikel i tidskrift","Refereegranskat","eng","Journal of the American Chemical Society","0002-7863","1520-5126","published","139","40","","14129","14136","2017","","","","AMER CHEMICAL SOC","","","","","","","10.1021/jacs.7b06406","000413057100032","28889740","","urn:nbn:se:liu:diva-142425","","","","Annan kemi (10499)","","","<p>Funding Agencies|Spanish Ministerio de Economia y Competitividad (MINECO) [RYC-2012-11133, FIS 2013-40667-P, CTQ2014-52869-P, FIS 2015-67287-P]; Comunidad de Madrid [S2013/MIT-2841, S2013/MIT-3007]; European Union; Russian Science Foundation [1423-00204-P]</p>","<p>Expanded porphyrins are large-cavity macro cycles with enormous potential in coordination chemistry, anion sensing, photodynamic therapy, and optoelectronics. In the last two decades, the surface science community has assessed the physicochemical properties of tetrapyrrolic-like macrocydes. However, to date, the sublimation, self-assembly and atomistic insights of expanded porphyrins on surfaces have remained elusive. Here, we show the self-assembly on Au(111) of an expanded aza-porphyrin, namely, an ""expanded hemi-spatially-controlled porphyrazine"", through a unique growth mechanism based on deprotonation long-range orientational self-assembly. Furthermore, a spatially controlled ""writing"" protocol on such self-assembled architecture is presented based on the STM tip-induced deprotonation of the inner protons of individual macrocydes. Finally, the capability of these surface-confined macrocydes to host lanthanide elements is assessed, introducing a novel off-centered coordination motif. The presented findings represent a milestone in the fields of porphyrinoid chemistry and surface science, revealing a great potential for novel surface patterning, opening new avenues for molecular level information storage, and boosting the emerging field of surface-confined coordination chemistry involving f-block elements.</p>","","","","","","","","","","","","","2017-10-31","2017-10-31","2017-10-31","","","12","","2","","","","","","false","","",""
"1135457","Fashandi, Hossein [hosfa18] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Dahlqvist, Martin [marda09] [0000-0001-5036-2833] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Lu, Jun [junlu07] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Palisaitis, Justinas [juspa01] [0000-0003-3203-7935] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Simak, Sergey [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Rosén, Johanna [johro07] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Hultman, Lars [larhu75] [0000-0002-2837-3656] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Andersson, Mike [mikan22] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tillämpad sensorvetenskap [11901]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Lloyd Spetz, Anita [anill63] [0000-0002-2817-3574] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tillämpad sensorvetenskap [11901]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Eklund, Per [perek02] [0000-0003-1785-0864] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Synthesis of Ti3AuC2, Ti3Au2C2 and Ti3IrC2 by noble metal substitution reaction in Ti3SiC2 for high-temperature-stable Ohmic contacts to SiC","Artikel i tidskrift","Refereegranskat","eng","Nature Materials","1476-1122","1476-4660","published","16","8","","814","818","2017","","","","NATURE PUBLISHING GROUP","","","","","","","10.1038/NMAT4896","000406424600012","28459444","","urn:nbn:se:liu:diva-139912","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|VINN Excellence Center in research and innovation on Functional Nanoscale Materials (FunMat) by the Swedish Governmental Agency for Innovation Systems (VINNOVA); Swedish Government Strategic Research Areas in Materials Science on Functional Materials at Linkoping University [2009 00971]; Swedish Foundation for Strategic Research through the Future Research Leaders 5 Program; Synergy Grant FUNCASE, Functional Carbides and Advanced Surface Engineering; e-Science Research Centre (SeRC); Swedish Research Council (VR) [2014-4750]; European Research Council under the European Community [335383]; Knut and Alice Wallenberg Foundation</p>","<p>The large class of layered ceramics encompasses both van der Waals (vdW) and non-vdW solids. While intercalation of noble metals in vdW solids is known, formation of compounds by incorporation of noble-metal layers in non-vdW layered solids is largely unexplored. Here, we show formation of Ti3AuC2 and Ti3Au2C2 phases with up to 31% lattice swelling by a substitutional solid-state reaction of Au into Ti3SiC2 single-crystal thin films with simultaneous out-diffusion of Si. Ti3IrC2 is subsequently produced by a substitution reaction of Ir for Au in Ti3Au2C2. These phases form Ohmic electrical contacts to SiC and remain stable after 1,000 h of ageing at 600 degrees C in air. The present results, by combined analytical electron microscopy and ab initio calculations, open avenues for processing of noble-metal-containing layered ceramics that have not been synthesized from elemental sources, along with tunable properties such as stable electrical contacts for high-temperature power electronics or gas sensors.</p>","","","","","","","","","","","","","2017-08-23","2017-08-23","2017-11-03","http://liu.diva-portal.org/smash/get/diva2:1135457/FULLTEXT01.pdf","","11","","2","","","","","","false","","",""
"1078843","Finzel, Kati [katfi97] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","About the compatibility between ansatzes and constraints for a local formulation of orbital-free density functional theory","Artikel i tidskrift","Refereegranskat","eng","International Journal of Quantum Chemistry","0020-7608","1097-461X","published","117","5","","","","2017","","","","WILEY-BLACKWELL","","","","","","","10.1002/qua.25329","000392757200002","","","urn:nbn:se:liu:diva-134796","","","orbital-free density functional theory; one-point functionals; local density approximation; Pauli potential; non-analytical functional","Teoretisk kemi (10407)","","","<p>Funding Agencies|Alexander von Humboldt foundation; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [Faculty Grant SFO Mat LiU No 2009 00971]</p>","<p>Functional properties that are exact for the Hohenberg-Kohn functional may turn into mutually exclusive constraints at a given level of ansatz. This is exemplarily shown for the local density approximation. Nevertheless, it is possible to reach exactly the Kohn-Sham data from an orbital-free density functional framework based on simple one-point functionals by starting from the Levy-Perdew-Sahni formulation. The energy value is obtained from the density-potential pair, and therefore does not refer to the functional dependence of the potential expression. Consequently, the potential expression can be obtained from any suitable model and is not required to follow proper scaling behavior.</p>","","","","","","","","","","","","","2017-03-06","2017-03-06","2017-11-29","","","1","","1","","","","","UNSP e25329","false","","",""
"1060905","Brodin, Gert (Umeå University, Sweden);Stenflo, Lennart [lenst65] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Juul Rasmussen, Jens (Technical University of Denmark, Denmark)","Focus issue to honour Hans L Pecseli on his 70th birthday","Artikel i tidskrift","Övrigt vetenskapligt","eng","Physica Scripta","0031-8949","1402-4896","published","92","1","","","","2017","","","","IOP PUBLISHING LTD","","","","","","","10.1088/0031-8949/92/1/010301","000389326000001","","","urn:nbn:se:liu:diva-133500","","","","Fysik (103)","","","","<p>n/a</p>","","","","","","","","","","","","","2016-12-29","2016-12-30","2017-11-29","","","3","","1","","editorialMaterial","","","010301","false","","",""
"1060097","Finzel, Kati [katfi97] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Baranov, Alexey I. (Max Planck Institute Chemistry Phys Solids, Germany)","A simple model for the Slater exchange potential and its performance for solids","Artikel i tidskrift","Refereegranskat","eng","International Journal of Quantum Chemistry","0020-7608","1097-461X","published","117","1","","40","47","2017","","","","WILEY-BLACKWELL","","","","","","","10.1002/qua.25312","000388601500006","","","urn:nbn:se:liu:diva-133370","","","band gaps; exchange potential; Slater potential","Teoretisk kemi (10407)","","","<p>Funding Agencies|Alexander von Humboldt foundation; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; Deutsche Forschungsgemeinschaft [DFG BA-4911/1-1]</p>","<p>A simple local model for the Slater exchange potential is determined by least square fit procedure from Hartree-Fock (HF) atomic data. Since the Slater potential is the exact exchange potential yielding HF electron density from Levy-Perdew-Sahni density functional formalism (Levy et al., Phys. Rev. A 1984, 30, 2745), the derived local potential is significantly more negative than the conventional local density approximation. On the set of 22 ionic, covalent and van der Waals solids including strongly correlated transition metal oxides, it has been demonstrated, that this simple model potential is capable of reproducing the band gaps nearly as good as popular meta GGA potentials in close agreement with experimental values.</p>","","","","","","","","","","","","","2016-12-22","2016-12-27","2017-11-29","","","2","","1","","","","","","false","","",""
"1135446","Green, B. L. (University of Warwick, England);Breeze, B. G. (University of Warwick, England);Rees, G. J. (University of Warwick, England);Hanna, J. V. (University of Warwick, England);Chou, J. -P. (Hungarian Academic Science, Hungary);Ivady, Viktor [vikiv58] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Hungarian Academic Science, Hungary);Gali, A. (Hungarian Academic Science, Hungary; Budapest University of Technology and Econ, Hungary);Newton, M. E. (University of Warwick, England)","All-optical hyperpolarization of electron and nuclear spins in diamond","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","96","5","","","","2017","","","College Park","American Physical Society","","","","","","","10.1103/PhysRevB.96.054101","000406671100001","","","urn:nbn:se:liu:diva-139914","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Engineering and Physical Sciences Research Council [EP/M013243/1, EP/J500045/1]; Gemological Institute of America; EU Commission (FP7 DIADEMS Project) [611143]</p>","<p>Low thermal polarization of nuclear spins is a primary sensitivity limitation for nuclear magnetic resonance. Here we demonstrate optically pumped (microwave-free) nuclear spin polarization of C-13 and N-15 in N-15-doped diamond. (15)Npolarization enhancements up to- 2000 above thermal equilibrium are observed in the paramagnetic system Ns(0). Nuclear spin polarization is shown to diffuse to bulk C-13 with NMR enhancements of -200 at room temperature and -500 at 240 K, enabling a route to microwave-free high-sensitivity NMR study of biological samples in ambient conditions.</p>","","","","","","","","","","","","","2017-08-23","2017-08-23","2017-11-29","http://liu.diva-portal.org/smash/get/diva2:1135446/FULLTEXT01.pdf","","8","","0","","","","","054101","true","","",""
"1120979","Christle, David J. (University of Chicago, IL 60637 USA);Klimov, Paul V. (University of Chicago, IL 60637 USA);de las Casas, Charles F. (University of Chicago, IL 60637 USA);Szasz, Krisztian (Hungarian Academic Science, Hungary);Ivády, Viktor [vikiv58] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Hungarian Academic Science, Hungary);Jokubavicius, Valdas [valjo12] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Ul-Hassan, Jawad [jawul47] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Syväjärvi, Mikael [miksy08] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Koehl, William F. (University of Chicago, IL 60637 USA);Ohshima, Takeshi (National Institute Quantum and Radiol Science and Technology, Japan);Nguyen, Son Tien [nguso90] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Janzén, Erik [erija14] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Halvledarmaterial [2218]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Gali, Adam (Hungarian Academic Science, Hungary; Budapest University of Technology and Econ, Hungary);Awschalom, David D. (University of Chicago, IL 60637 USA)","Isolated Spin Qubits in SiC with a High-Fidelity Infrared Spin-to-Photon Interface","Artikel i tidskrift","Refereegranskat","eng","Physical Review X","2160-3308","2160-3308","published","7","2","","","","2017","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevX.7.021046","000404032900001","","","urn:nbn:se:liu:diva-139278","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|ARO [W911NF-15-2-0058]; AFOSR [FA9550-15-1-0029, FA9550-14-1-0231]; NSF MRSEC [DMR-1420709]; DOE LDRD Program; Swedish Research Council [621-2014-5825, 2016-04068]; AForsk foundation [16-576]; Carl-Trygger Stiftelse for Vetenskaplig Forskning [CTS 15:339]; Knut and Alice Wallenberg Foundation [KAW 2013.0300]; JSPS [26286047]; Swedish Energy Agency [43611-1]</p>","<p>The divacancies in SiC are a family of paramagnetic defects that show promise for quantum communication technologies due to their long-lived electron spin coherence and their optical addressability at near-telecom wavelengths. Nonetheless, a high-fidelity spin-photon interface, which is a crucial prerequisite for such technologies, has not yet been demonstrated. Here, we demonstrate that such an interface exists in isolated divacancies in epitaxial films of 3C-SiC and 4H-SiC. Our data show that divacancies in 4H-SiC have minimal undesirable spin mixing, and that the optical linewidths in our current sample are already similar to those of recent remote entanglement demonstrations in other systems. Moreover, we find that 3C-SiC divacancies have a millisecond Hahn-echo spin coherence time, which is among the longest measured in a naturally isotopic solid. The presence of defects with these properties in a commercial semiconductor that can be heteroepitaxially grown as a thin film on Si shows promise for future quantum networks based on SiC defects.</p>","","","","","","","","","","","","","2017-07-07","2017-07-07","2017-11-29","http://liu.diva-portal.org/smash/get/diva2:1120979/FULLTEXT01.pdf","","14","","0","","","","","21046","false","","",""
"1120187","Aschebrock, Thilo (University of Bayreuth, Germany);Armiento, Rickard [ricar47] [0000-0002-5571-0814] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Kuemmel, Stephan (University of Bayreuth, Germany)","Orbital nodal surfaces: Topological challenges for density functionals","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","95","24","","","","2017","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.95.245118","000403355300004","","","urn:nbn:se:liu:diva-139184","","","","Teoretisk kemi (10407)","","","<p>Funding Agencies|German-Israeli Foundation for Scientific Research and Development; University of Bayreuth Graduate School; Swedish Research Council (VR) [2016-04810]; Swedish e-Science Research Centre (SeRC)</p>","<p>Nodal surfaces of orbitals, in particular of the highest occupied one, play a special role in Kohn-Sham density-functional theory. The exact Kohn-Sham exchange potential, for example, shows a protruding ridge along such nodal surfaces, leading to the counterintuitive feature of a potential that goes to different asymptotic limits in different directions. We show here that nodal surfaces can heavily affect the potential of semilocal density-functional approximations. For the functional derivatives of the Armiento-Kummel (AK13) [Phys. Rev. Lett. 111, 036402 (2013)] and Becke88 [Phys. Rev. A 38, 3098 (1988)] energy functionals, i.e., the corresponding semilocal exchange potentials, as well as the Becke-Johnson [J. Chem. Phys. 124, 221101 (2006)] and van Leeuwen-Baerends (LB94) [Phys. Rev. A 49, 2421 (1994)] model potentials, we explicitly demonstrate exponential divergences in the vicinity of nodal surfaces. We further point out that many other semilocal potentials have similar features. Such divergences pose a challenge for the convergence of numerical solutions of the Kohn-Sham equations. We prove that for exchange functionals of the generalized gradient approximation (GGA) form, enforcing correct asymptotic behavior of the potential or energy density necessarily leads to irregular behavior on or near orbital nodal surfaces. We formulate constraints on the GGA exchange enhancement factor for avoiding such divergences.</p>","","","","","","","","","","","","","2017-07-05","2017-07-05","2017-11-29","http://liu.diva-portal.org/smash/get/diva2:1120187/FULLTEXT01.pdf","","3","","0","","","","","245118","false","","",""
"1089979","Sun, Weiwei (Uppsala University, Sweden; KTH Royal Institute Technology, Sweden);Luo, Wei (Uppsala University, Sweden);Feng, Qingguo [qinfe69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska högskolan [1751]);Ahuja, Rajeev (Uppsala University, Sweden; KTH Royal Institute Technology, Sweden)","Anisotropic distortion and Lifshitz transition in alpha-Hf under pressure","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","95","11","","","","2017","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.95.115130","000396273400004","","","urn:nbn:se:liu:diva-136595","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Swedish Research Council (V.R.); CSC scholarship</p>","<p>In this work we report a theoretical investigation on behavior of the elastic constant C-44 and the transverse optical phonon mode E(2)g of a-Hf under pressure within the density functional theory. In contrast to many other reported transition metals, the above two quantities do not show a synchronous relation as pressure increases. Below 13 GPa, an opposite shifting tendency has been observed. However, once the pressure is raised above 13 GPa, the trend is pulled back to be consistent. This anomalous behavior is figured out to be caused by the large lattice anisotropy of the c/a ratio along with the elastic anisotropy. The synchronous behavior is found to be in accordance with the behavior of c/a ratio with increased pressure. In our band-structure investigations the electronic topological transition has been discovered at 10 GPa, which relates to the change of c/a ratio suggested by recent literature. The presence of the Van Hove singularity shown in the densities of states has been identified and regarded as the origin of the variation of C-44 and E(2)g.</p>","","","","","","","","","","","","","2017-04-21","2017-04-21","2017-11-29","http://liu.diva-portal.org/smash/get/diva2:1089979/FULLTEXT01.pdf","","4","","0","","","","","115130","false","","",""
"1151695","Golosova, N. O. (Joint Institute Nucl Research, Russia);Kozlenko, D. P. (Joint Institute Nucl Research, Russia);Dubrovinsky, L. S. (University of Bayreuth, Germany);Cerantola, V. (European Synchrotron Radiat Facil, France);Bykov, M. (University of Bayreuth, Germany);Bykova, E. (University of Bayreuth, Germany; DESY, Germany);Kichanov, S. E. (Joint Institute Nucl Research, Russia);Lukin, E. V. (Joint Institute Nucl Research, Russia);Savenko, B. N. (Joint Institute Nucl Research, Russia);Ponomareva, A. V. (National University of Science and Technology MISIS, Russia);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Magnetic and structural properties of FeCO3 at high pressures","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","96","13","","","","2017","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.96.134405","000412054400003","","","urn:nbn:se:liu:diva-142153","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Ministry of Education and Science of the Russian Federation [14.Y26.31.0005]; Swedish Research Council [2015-04391]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkping University [2009 00971]</p>","<p>The structural and magnetic properties of siderite FeCO3 have been studied by means of neutron powder diffraction at pressures up to 7.5 GPa and first-principles theoretical calculations. The lattice compression in the rhombohedral calcite-type structure is dominated by the reduction of the Fe-O bonds, while the changes of the C-O bonds are much less pronounced. The Neel temperature of the antiferromagnetic ( AFM) ground state increases substantially under pressure with a coefficient dT(N)/dP = 1.8K/GPa, which is about 1.5 times larger in comparison with those predicted by the empirical Bloch rule. The ab initio calculations were performed in the framework of the density functional theory including Hubbard-U correction. The calculated structural parameters and Neel temperature as functions of pressure provide a reasonable agreement with the experimental results. The analysis of the density of electronic states points toward increased covalent bonding between the Fe and O atoms upon pressure, giving rise to unexpectedly large pressure coefficient of the Neel temperature and reduced ordered magnetic moments of Fe atoms.</p>","","","","","","","","","","","","","2017-10-24","2017-10-24","2017-11-29","http://liu.diva-portal.org/smash/get/diva2:1151695/FULLTEXT01.pdf","","11","","0","","","","","134405","false","","",""
"1142320","Leonov, I. (University of Augsburg, Germany; National University of Science and Technology MISIS, Russia);Ponomareva, A. V. (National University of Science and Technology MISIS, Russia);Nazarov, R. (Lawrence Livermore National Lab, CA 94551 USA);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Pressure-induced spin-state transition of iron in magnesiowustite (Fe,Mg)O","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","96","7","","","","2017","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.96.075136","000407778300001","","","urn:nbn:se:liu:diva-140967","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|Deutsche Forschungsgemeinschaft [Transregio TRR 80]; Ministry of Education and Science of the Russian Federation [K3-2016-027]; Russian Foundation for Basic Researches [16-02-00797]; Swedish Research Council (VR) [2015-04391]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]</p>","<p>We present a detailed theoretical study of the electronic, magnetic, and structural properties of magnesiowustite Fe-1 Mg-x(x) O with x in the range between 0 and 0.875 using a fully charge self-consistent implementation of the density functional theory plus dynamical mean-field theory method. In particular, we compute the electronic structure and phase stability of the rocksalt B1-structured (Fe,Mg) O at high pressures relevant for the Earths lower mantle. We find that upon compression paramagnetic (Fe,Mg) O exhibits a spin-state transition of Fe2+ ions from a high-spin to low-spin (HS-LS) state which is accompanied by a collapse of local magnetic moments. The HS-LS transition results in a substantial drop in the lattice volume by about 4%-8%, implying a complex interplay between electronic and lattice degrees of freedom. Our results reveal a strong sensitivity of the calculated transition pressure P-tr. upon addition of Mg. While, for Fe-rich magnesiowustite with Mg x amp;lt; 0.5, Ptr. is about 80 GPa, for Mg x = 0.75 it drops to 52 GPa, i. e., by 35%. This behavior is accompanied by a substantial change in the spin transition range from 50 to 140 GPa in FeO to 30 to 90 GPa for x = 0.75. In addition, the calculated bulk modulus (in the HS state) is found to increase by similar to 12% from 142 GPa in FeO to 159 GPa in (Fe,Mg) O with Mg x = 0.875. We find that the pressure-induced HS-LS transition has different consequences for the electronic properties of the Fe-rich and -poor (Fe,Mg) O. For the Fe-rich (Fe,Mg) O, the transition is found to be accompanied by a Mott insulator to a (semi) metal phase transition. In contrast to that, for x amp;gt; 0.25, (Fe,Mg) O remains insulating up to the highest studied pressures, implying a Mott-insulator to band-insulator phase transition at the HS-LS transformation.</p>","","","","","","","","","","","","","2017-09-19","2017-09-19","2017-11-29","http://liu.diva-portal.org/smash/get/diva2:1142320/FULLTEXT01.pdf","","4","","0","","","","","075136","false","","",""
"1140139","Aschebrock, Thilo (University of Bayreuth, Germany);Armiento, Rickard [ricar47] [0000-0002-5571-0814] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Kuemmel, Stephan (University of Bayreuth, Germany)","Challenges for semilocal density functionals with asymptotically nonvanishing potentials","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","96","7","","","","2017","","","","AMER PHYSICAL SOC","","","","","","","10.1103/PhysRevB.96.075140","000407993900001","","","urn:nbn:se:liu:diva-140510","","","","Annan fysik (10399)","","","<p>Funding Agencies|German-Israeli Foundation for Scientific Research and Development; University of Bayreuth Graduate School; Swedish Research Council (V.R.) [2016-04810]; Swedish e-Science Research Centre (SeRC)</p>","<p>The Becke-Johnson model potential [A. D. Becke and E. R. Johnson, J. Chem. Phys. 124, 221101 ( 2006)] and the potential of the AK13 functional [R. Armiento and S. Kummel, Phys. Rev. Lett. 111, 036402 ( 2013)] have been shown to mimic features of the exact Kohn-Sham exchange potential, such as step structures that are associated with shell closings and particle-number changes. A key element in the construction of these functionals is that the potential has a limiting value far outside a finite system that is a system-dependent constant rather than zero. We discuss a set of anomalous features in these functionals that are closely connected to the nonvanishing asymptotic potential. The findings constitute a formidable challenge for the future development of semilocal functionals based on the concept of a nonvanishing asymptotic constant.</p>","","","","","","","","","","","","","2017-09-11","2017-09-11","2017-11-29","http://liu.diva-portal.org/smash/get/diva2:1140139/FULLTEXT01.pdf","","3","","0","","","","","075140","false","","",""
"1153703","Ivády, Viktor [vikiv58] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Hungarian Academic Science, Hungary);Gali, Adam (Hungarian Academic Science, Hungary; Budapest University of Technology and Econ, Hungary);Abrikosov, Igor [igoab43] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (National University of Science and Technology MISIS, Russia)","Hybrid-DFT + V-w method for band structure calculation of semiconducting transition metal compounds: the case of cerium dioxide","Artikel i tidskrift","Refereegranskat","eng","Journal of Physics: Condensed Matter","0953-8984","1361-648X","published","29","45","","","","2017","","","","IOP PUBLISHING LTD","","","","","","","10.1088/1361-648X/aa8b93","000412945900001","28891806","","urn:nbn:se:liu:diva-142418","","","hybrid functional; transition metal oxide; quasi-particle equation; orbital dependent potential correction","Teoretisk kemi (10407)","","","<p>Funding Agencies|Knut and Alice Wallenberg Foundation; Ministry of Education and Science of the Russian Federation [14.Y26.31.0005]; Hungarian Academy of Sciences</p>","<p>Hybrid functionals non-local exchange-correlation potential contains a derivative discontinuity that improves on standard semi-local density functional theory (DFT) band gaps. Moreover, by careful parameterization, hybrid functionals can provide self-interaction reduced description of selected states. On the other hand, the uniform description of all the electronic states of a given system is a known drawback of these functionals that causes varying accuracy in the description of states with different degrees of localization. This limitation can be remedied by the orbital dependent exact exchange extension of hybrid functionals; the hybrid-DFT + V-w method (Ivady et al 2014 Phys. Rev. B 90 035146). Based on the analogy of quasi-particle equations and hybrid-DFT single particle equations, here we demonstrate that parameters of hybrid-DFT + V-w functional can be determined from approximate theoretical quasi-particle spectra without any fitting to experiment. The proposed method is illustrated on the charge self-consistent electronic structure calculation for cerium dioxide where itinerant valence states interact with well-localized 4f atomic like states, making this system challenging for conventional methods, either hybrid-DFT or LDA + U, and therefore allowing for a demonstration of the advantages of the proposed scheme.</p>","","","","","","","","","","","","","2017-10-31","2017-10-31","2017-12-01","","","3","","1","","","","","454002","false","","",""
"1160463","Kerdsongpanya, Sit [sitke04] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Rensselaer Polytech Institute, NY 12180 USA);Hellman, Olle [olohe96] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (CALTECH, CA 91125 USA);Sun, Bo (National University of Singapore, Singapore);Kan Koh, Yee (National University of Singapore, Singapore);Lu, Jun [junlu07] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Van Nong, Ngo (Department of Energy Conversion and Storage, Technical University of Denmark, Risø Campus, Roskilde, Denmark);Simak, Sergei I. [sersi78] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]);Alling, Björn [bjoal69] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Teoretisk Fysik [2229]) (Linköpings universitet [276], Tekniska fakulteten [872902]) (Max Planck Institute Eisenforsch GmbH, Germany);Eklund, Per [perek02] [0000-0003-1785-0864] (Linköpings universitet [276], Institutionen för fysik, kemi och biologi [282], Tunnfilmsfysik [2232]) (Linköpings universitet [276], Tekniska fakulteten [872902])","Phonon thermal conductivity of scandium nitride for thermoelectrics from first-principles calculations and thin-film growth","Artikel i tidskrift","Refereegranskat","eng","Physical Review B","2469-9950","2469-9969","published","96","19","","","","2017","","","","American Physical Society","","","","","","","10.1103/PhysRevB.96.195417","000414738200008","","","urn:nbn:se:liu:diva-143238","","","","Den kondenserade materiens fysik (10304)","","","<p>Funding Agencies|European Research Council under the European Communitys Seventh Framework Programme [FP/2007-2013]; ERC [335383]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; Swedish Research Council [2012-4430, 2016-03365, 330-2014-6336, 2014-4750, 637-2013-7296]; Linnaeus Environment LiLi-NFM; Swedish Foundation for Strategic Research (SSF) through the Future Research Leaders 5 Program; NanoCaTe project (FP7) [604647]; National University of Singapore Startup Grant</p>","<p>The knowledge of lattice thermal conductivity of materials under realistic conditions is vitally important since many modern technologies require either high or low thermal conductivity. Here, we propose a theoretical model for determining lattice thermal conductivity, which takes into account the effect of microstructure. It is based on ab initio description that includes the temperature dependence of the interatomic force constants and treats anharmonic lattice vibrations. We choose ScN as a model system, comparing the computational predictions to the experimental data by time-domain thermoreflectance. Our experimental results show a trend of reduction in lattice thermal conductivity with decreasing domain size predicted by the theoretical model. These results suggest a possibility to control thermal conductivity by microstructural tailoring and provide a predictive tool for the effect of the microstructure on the lattice thermal conductivity of materials based on ab initio calculations.</p>","","","","","","","","","","","","","2017-11-27","2017-11-27","2017-12-05","http://liu.diva-portal.org/smash/get/diva2:1160463/FULLTEXT01.pdf","","9","","2","","","","","195417","true","","",""
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