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Bian Y, Chen X, Du S, Zhang Z, Hou J, Nie K, Guo Z, Dong H, Qiu Z, Chen N, Chen J. Revealing the Role of the Tetragonal Distortion in the Metal-Insulator Transition of Co- and Fe-Doped NiS. J Phys Chem Lett 2024; 15:1449-1454. [PMID: 38291988 DOI: 10.1021/acs.jpclett.3c03496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
Although the NiS exhibits the most widely adjustable metal-to-insulator (MIT) properties among the chalcogenides, the mechanisms, with respect to the regulations in their critical temperatures (TMIT), are yet unclear. Herein, we demonstrate the overlooked role associated with the structurally tetragonal distortion in elevating the TMIT of NiS; this is in distinct contrast to the previously expected hybridization and bandwidth regulations that usually reduces TMIT. Compared to the perspective of structure distortions, the orbital hybridization and band regulation of NiS are ∼19 times more effective adjustment in TMIT. As a result, the respective abruptions in both the electrical and thermal resistive switches across the TMIT of NiS can be better preserved in the low-temperature range (<273 K), shedding light on their optimum usage at cryogenic temperatures.
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Affiliation(s)
- Yi Bian
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Xing Chen
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Shuyu Du
- School of Renewable Energy, North China Electric Power University, Beijing 102206, China
| | - Ziyou Zhang
- Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China
| | - Jintao Hou
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Kaiqi Nie
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Zhiying Guo
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Hongliang Dong
- Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China
| | - Zhiyong Qiu
- School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, China
| | - Nuofu Chen
- School of Renewable Energy, North China Electric Power University, Beijing 102206, China
| | - Jikun Chen
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
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2
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Song R, Wang B, Feng K, Yao J, Lu M, Bai J, Dong S, An M. Structural dimerization and charge-orbital ordering in a ferromagnetic semiconductor LiV 2S 4 monolayer. Phys Chem Chem Phys 2023; 26:261-266. [PMID: 38055329 DOI: 10.1039/d3cp04560a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/08/2023]
Abstract
With the rise of two-dimensional (2D) materials, unique properties that are completely distinct from bulk counterparts continue to emerge at low-dimensional scales, presenting numerous opportunities and challenges. It also provides a new perspective for the study of transition metal systems. Here, based on density functional theory (DFT), the physical properties of 2D monolayer LiV2S4 have been studied. Remarkable changes have been observed, i.e., vanadium dimerization, ferromagnetism, charge distribution and metal-insulator transition (MIT). It is argued that the electronic instability leads to the V dimerization, which further lifts the degeneracy of charge distribution and stabilizes the charge and spin ordering state.
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Affiliation(s)
- Rui Song
- Department of General Education, Army Engineering University of People's Liberation Army, Nanjing 211101, China
| | - Bili Wang
- Department of General Education, Army Engineering University of People's Liberation Army, Nanjing 211101, China
| | - Kai Feng
- Department of General Education, Army Engineering University of People's Liberation Army, Nanjing 211101, China
| | - Jia Yao
- Department of General Education, Army Engineering University of People's Liberation Army, Nanjing 211101, China
| | - Mengjie Lu
- Department of General Education, Army Engineering University of People's Liberation Army, Nanjing 211101, China
| | - Jing Bai
- Department of General Education, Army Engineering University of People's Liberation Army, Nanjing 211101, China
| | - Shuai Dong
- School of Physics, Southeast University, Nanjing 211189, China.
| | - Ming An
- School of Physics, Southeast University, Nanjing 211189, China.
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3
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Nocerino E, Witteveen C, Kobayashi S, Forslund OK, Matsubara N, Zubayer A, Mazza F, Kawaguchi S, Hoshikawa A, Umegaki I, Sugiyama J, Yoshimura K, Sassa Y, von Rohr FO, Månsson M. Nuclear and magnetic spin structure of the antiferromagnetic triangular lattice compound LiCrTe 2 investigated by [Formula: see text]SR, neutron and X-ray diffraction. Sci Rep 2022; 12:21657. [PMID: 36522382 PMCID: PMC9755140 DOI: 10.1038/s41598-022-25921-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 12/07/2022] [Indexed: 12/23/2022] Open
Abstract
Two-dimensional (2D) triangular lattice antiferromagnets (2D-TLA) often manifest intriguing physical and technological properties, due to the strong interplay between lattice geometry and electronic properties. The recently synthesized 2-dimensional transition metal dichalcogenide LiCrTe[Formula: see text], being a 2D-TLA, enriched the range of materials which can present such properties. In this work, muon spin rotation ([Formula: see text]SR) and neutron powder diffraction (NPD) have been utilized to reveal the true magnetic nature and ground state of LiCrTe[Formula: see text]. From high-resolution NPD the magnetic spin order at base-temperature is not, as previously suggested, helical, but rather collinear antiferromagnetic (AFM) with ferromagnetic (FM) spin coupling within the ab-plane and AFM coupling along the c-axis. The value if the ordered magnetic Cr moment is established as [Formula: see text]. From detailed [Formula: see text]SR measurements we observe an AFM ordering temperature [Formula: see text] K. This value is remarkably higher than the one previously reported by magnetic bulk measurements. From [Formula: see text]SR we are able to extract the magnetic order parameter, whose critical exponent allows us to categorize LiCrTe[Formula: see text] in the 3D Heisenberg AFM universality class. Finally, by combining our magnetic studies with high-resolution synchrotron X-ray diffraction (XRD), we find a clear coupling between the nuclear and magnetic spin lattices. This suggests the possibility for a strong magnon-phonon coupling, similar to what has been previously observed in the closely related compound LiCrO[Formula: see text].
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Affiliation(s)
- E. Nocerino
- KTH Royal Institute of Technology, Department of Applied Physics, Alba Nova University Center, 114 21 Stockholm, Sweden
| | - C. Witteveen
- Department of Quantum Matter Physics, University of Geneva, 24 Quai Ernest-Ansermet, 1211 Geneva 4, Switzerland
- Department of Physics, University of Zürich, Winterthurerstr. 190, 8057 Zurich, Switzerland
| | - S. Kobayashi
- Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1 Kouto, Sayo, 679-5198 Japan
| | - O. K. Forslund
- Department of Physics, Chalmers University of Technology, 412 96 Göteborg, Sweden
| | - N. Matsubara
- KTH Royal Institute of Technology, Department of Applied Physics, Alba Nova University Center, 114 21 Stockholm, Sweden
| | - A. Zubayer
- Department of Physics, Chemistry and Biology (IFM), Linköping University, 581 83 Linköping, Sweden
| | - F. Mazza
- Insitute of Solid State Physics, TU Wien, Wiedner Haupstraße 8-10, 1040 Vienna, Austria
| | - S. Kawaguchi
- Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1 Kouto, Sayo, 679-5198 Japan
| | - A. Hoshikawa
- Frontier Research Center for Applied Atomic Sciences, Ibaraki University, 162-1 Shirakata, Tokai, Ibaraki 319-1106 Japan
| | - I. Umegaki
- Muon Science Laboratory, Institute of Materials Structure Science, KEK, Tokai, Ibaraki 319-1106 Japan
| | - J. Sugiyama
- Neutron Science and Technology Center, Comprehensive Research Organization for Science and Society (CROSS), Tokai, Ibaraki 319-1106 Japan
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 Japan
| | - K. Yoshimura
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, 606-8502 Japan
| | - Y. Sassa
- Department of Physics, Chalmers University of Technology, 412 96 Göteborg, Sweden
| | - F. O. von Rohr
- Department of Quantum Matter Physics, University of Geneva, 24 Quai Ernest-Ansermet, 1211 Geneva 4, Switzerland
| | - M. Månsson
- KTH Royal Institute of Technology, Department of Applied Physics, Alba Nova University Center, 114 21 Stockholm, Sweden
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4
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Ohkubo I, Mori T. Rational Design of 3d Transition-Metal Compounds for Thermoelectric Properties by Using Periodic Trends in Electron-Correlation Modulation. J Am Chem Soc 2022; 144:3590-3602. [PMID: 35170313 DOI: 10.1021/jacs.1c12520] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The electronic structures in solid-state transition-metal compounds can be represented by two parameters: the charge-transfer energy (Δ), which is the energy difference between the p-band of an anion and an upper Hubbard band contributed by transition-metal d-orbitals, and the onsite Coulomb repulsion energy (U), which represents the energy difference between lower and upper Hubbard bands composed of split d-orbitals in transition metals. These parameters can facilitate the classification of various types of electronic structures. In this study, the dependences of anion species (N3-, P3-, As3-, O2-, S2-, Se2-, Te2-, F-, Cl-, Br-, and I-) on Δ and U of 566 different binary and ternary 3d transition-metal compounds were investigated using ionic-model calculations. We were able to identify the systematic chemical trends in the variations in Δ and U values with the anion species of 11 different families of 3d transition-metal compounds in a comprehensive manner. The effective use of Δ-U diagrams given here, to facilitate the discovery and development of functional compounds, was demonstrated on thermoelectric compounds by classifying the thermoelectric properties of 3d transition-metal compounds and by predicting unrealized high-performance thermoelectric compounds.
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Affiliation(s)
- Isao Ohkubo
- International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Takao Mori
- International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.,Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573, Japan
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Haraguchi Y, Arikai H, Katori HA. Metallic state in the vicinity of molecular orbital crystallization in the d1thiospinel ZnTi 2S 4prepared via a reductive ion-exchange reaction. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:395603. [PMID: 34252898 DOI: 10.1088/1361-648x/ac1369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 07/12/2021] [Indexed: 06/13/2023]
Abstract
A novel Ti3+-based thiospinel ZnTi2S4is successfully synthesized via a low-temperature ion-exchange reaction. ZnTi2S4shows a signature of metallic ground state evidenced by a contribution of conduction electrons in the heat capacity and Pauli-like paramagnetic susceptibility. These observations contrast to the electronic state of similar Ti3+-based spinel MgTi2O4exhibiting the metal-insulator transition associated with a molecular orbital crystallization (MOC). Furthermore, the magnetic susceptibility of ZnTi2S4shows a pseudogap-like behavior indicated by a vast peak in the magnetic susceptibility around 110 K, likely originating from the MOC fluctuation. The origin of the difference in the electronic states of MgTi2O4and ZnTi2S4would be due to the different magnitude of overlap between Ti 3dandporbitals (O: 2pand S: 3p). The presence of a MOC state in the close vicinity of insulator-metal transition may suggest the importance of itinerancy in a MOC.
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Affiliation(s)
- Yuya Haraguchi
- Department of Applied Physics and Chemical Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Hiroki Arikai
- Department of Applied Physics and Chemical Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Hiroko Aruga Katori
- Department of Applied Physics and Chemical Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
- Research Center for Thermal and Entropic Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
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6
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Khomskii DI, Mizokawa T, Streltsov SV. Comment on "Spin-Lattice Coupling and the Emergence of the Trimerized Phase in the S=1 Kagome Antiferromagnet Na_{2}Ti_{3}Cl_{8}". PHYSICAL REVIEW LETTERS 2021; 127:049701. [PMID: 34355926 DOI: 10.1103/physrevlett.127.049701] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 06/16/2021] [Indexed: 06/13/2023]
Affiliation(s)
- Daniel I Khomskii
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, D-50937 Köln, Germany
| | - Takashi Mizokawa
- Department of Applied Physics, Waseda University, Tokyo 169-8555, Japan
| | - Sergey V Streltsov
- Institute of Metal Physics, S. Kovalevskoy Street 18, 620990 Ekaterinburg, Russia
- Ural Federal University, Mira Street 19, 620002 Ekaterinburg, Russia
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7
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Khomskii DI, Streltsov SV. Orbital Effects in Solids: Basics, Recent Progress, and Opportunities. Chem Rev 2020; 121:2992-3030. [PMID: 33314912 DOI: 10.1021/acs.chemrev.0c00579] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The properties of transition metal compounds are largely determined by nontrivial interplay of different degrees of freedom: charge, spin, lattice, and also orbital ones. Especially rich and interesting effects occur in systems with orbital degeneracy. For example, they result in the famous Jahn-Teller effect, leading to a plethora of consequences for static and dynamic properties, including nontrivial quantum effects. In the present review, we discuss the main phenomena in the physics of such systems, paying central attention to the novel manifestations of those. After shortly summarizing the basic phenomena and their descriptions, we concentrate on several specific directions in this field. One of them is the reduction of effective dimensionality in many systems with orbital degrees of freedom due to the directional character of orbitals, with the concomitant appearance of some instabilities that lead in particular to the formation of dimers, trimers, and similar clusters in a material. The properties of such cluster systems, which are largely determined by their orbital structure, are discussed in detail, and many specific examples of those in different materials are presented. Another big field that has acquired special significance relatively recently is the role of the relativistic spin-orbit interaction. The mutual influence of this interaction and the more traditional Jahn-Teller physics is treated in detail in the second part of the review. In discussing all of these questions, special attention is paid to novel quantum effects.
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Affiliation(s)
- Daniel I Khomskii
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Straße 77, D-50937 Köln, Germany
| | - Sergey V Streltsov
- Institute of Metal Physics, S. Kovalevskoy St. 18, 620990 Ekaterinburg, Russia.,Department of Theoretical Physics and Applied Mathematics, Ural Federal University, Mira St. 19, 620002 Ekaterinburg, Russia
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8
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Okamoto Y, Amano H, Katayama N, Sawa H, Niki K, Mitoka R, Harima H, Hasegawa T, Ogita N, Tanaka Y, Takigawa M, Yokoyama Y, Takehana K, Imanaka Y, Nakamura Y, Kishida H, Takenaka K. Regular-triangle trimer and charge order preserving the Anderson condition in the pyrochlore structure of CsW 2O 6. Nat Commun 2020; 11:3144. [PMID: 32561729 PMCID: PMC7305186 DOI: 10.1038/s41467-020-16873-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 05/29/2020] [Indexed: 12/04/2022] Open
Abstract
Since the discovery of the Verwey transition in magnetite, transition metal compounds with pyrochlore structures have been intensively studied as a platform for realizing remarkable electronic phase transitions. We report on a phase transition that preserves the cubic symmetry of the β-pyrochlore oxide CsW2O6, where each of W 5d electrons are confined in regular-triangle W3 trimers. This trimer formation represents the self-organization of 5d electrons, which can be resolved into a charge order satisfying the Anderson condition in a nontrivial way, orbital order caused by the distortion of WO6 octahedra, and the formation of a spin-singlet pair in a regular-triangle trimer. An electronic instability due to the unusual three-dimensional nesting of Fermi surfaces and the strong correlations of the 5d electrons characteristic of the pyrochlore oxides are both likely to play important roles in this charge-orbital-spin coupled phenomenon.
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Affiliation(s)
- Yoshihiko Okamoto
- Department of Applied Physics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan.
| | - Haruki Amano
- Department of Applied Physics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
| | - Naoyuki Katayama
- Department of Applied Physics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
| | - Hiroshi Sawa
- Department of Applied Physics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
| | - Kenta Niki
- Department of Applied Physics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
| | - Rikuto Mitoka
- Department of Applied Physics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
| | - Hisatomo Harima
- Department of Physics, Kobe University, Rokkodai 1-1, Nada-ku, Kobe, 657-8501, Japan
| | - Takumi Hasegawa
- Graduate School of Integrated Arts and Sciences, Hiroshima University, Kagamiyama 1-7-1, Higashi-Hiroshima, 739-8521, Japan
| | - Norio Ogita
- Graduate School of Integrated Arts and Sciences, Hiroshima University, Kagamiyama 1-7-1, Higashi-Hiroshima, 739-8521, Japan
| | - Yu Tanaka
- Institute for Solid State Physics, University of Tokyo, Kashiwanoha 5-1-5, Kashiwa, 277-8581, Japan
| | - Masashi Takigawa
- Institute for Solid State Physics, University of Tokyo, Kashiwanoha 5-1-5, Kashiwa, 277-8581, Japan
| | - Yasunori Yokoyama
- Department of Applied Physics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
| | - Kanji Takehana
- National Institute for Materials Science (NIMS), Sakura 3-13, Tsukuba, 305-0003, Japan
| | - Yasutaka Imanaka
- National Institute for Materials Science (NIMS), Sakura 3-13, Tsukuba, 305-0003, Japan
| | - Yuto Nakamura
- Department of Applied Physics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
| | - Hideo Kishida
- Department of Applied Physics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
| | - Koshi Takenaka
- Department of Applied Physics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
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9
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Kobayashi S, Katayama N, Manjo T, Ueda H, Michioka C, Sugiyama J, Sassa Y, Forslund OK, Månsson M, Yoshimura K, Sawa H. Linear Trimer Formation with Antiferromagnetic Ordering in 1T-CrSe2 Originating from Peierls-like Instabilities and Interlayer Se–Se Interactions. Inorg Chem 2019; 58:14304-14315. [DOI: 10.1021/acs.inorgchem.9b00186] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Shintaro Kobayashi
- Department of Applied Physics, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan
| | - Naoyuki Katayama
- Department of Applied Physics, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan
| | - Taishun Manjo
- Department of Applied Physics, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan
| | - Hiroaki Ueda
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Chishiro Michioka
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Jun Sugiyama
- Toyota Central Research & Development Laboratories, Inc., Nagakute, Aichi 480-1192, Japan
| | - Yasmine Sassa
- Department of Physics & Astronomy, Uppsala University, Box 516, 751 20 Uppsala, Sweden
- Department of Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden
| | - Ola Kenji Forslund
- Department of Applied Physics, KTH Royal Institute of Technology, Electrum 229, SE-16440 Stockholm Kista, Sweden
| | - Martin Månsson
- Department of Applied Physics, KTH Royal Institute of Technology, Electrum 229, SE-16440 Stockholm Kista, Sweden
| | - Kazuyoshi Yoshimura
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
- Research Center for Low Temperature and Material Sciences, Kyoto University, Kyoto 606-8501, Japan
| | - Hiroshi Sawa
- Department of Applied Physics, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan
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10
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Talanov MV, Shirokov VB, Avakyan LA, Talanov VM, Borlakov KS. Vanadium clusters formation in geometrically frustrated spinel oxide AlV 2O 4. ACTA CRYSTALLOGRAPHICA SECTION B, STRUCTURAL SCIENCE, CRYSTAL ENGINEERING AND MATERIALS 2018; 74:337-353. [PMID: 30141419 DOI: 10.1107/s2052520618007242] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2017] [Accepted: 05/14/2018] [Indexed: 06/08/2023]
Abstract
The spinel oxide AlV2O4 is a unique material, in which the formation of clusters is accompanied by atomic, charge and orbital ordering and a rhombohedral lattice distortion. In this work a theory of the structural phase transition in AlV2O4 is proposed. This theory is based on the study of the order-parameter symmetry, thermodynamics, electron density distribution, crystal chemistry and mechanisms of formation of the atomic and orbital structures of the rhombohedral phase. It is established that the critical order parameter is transformed according to irreducible representation k9(τ4) (in Kovalev notation) of the Fd \bar{3}m space group. Knowledge of the order-parameter symmetry allows us to show that the derived AlV2O4 rhombohedral structure is a result of displacements of all atom types and the ordering of Al atoms (1:1 order type in tetrahedral spinel sites), V atoms (1:1:6 order type in octahedral sites) and O atoms (1:1:3:3 order type), and the ordering of dxy, dxz and dyz orbitals. Application of the density functional theory showed that V atoms in the Kagomé sublattice formed separate trimers. Also, no sign of metallic bonding between separate vanadium trimers in the heptamer structure was found. The density functional theory study and the crystal chemical analysis of V-O bond lengths allowed us to assume the existence of dimers and trimers as main clusters in the structure of the AlV2O4 rhombohedral modification. The trimer model of the low-symmetry AlV2O4 structure is proposed. Within the Landau theory of phase transitions, typical diagrams of possible phase states are built. It is shown that phase states can be changed as a first-order phase transition close to the second order in the vicinity of tricritical points of the phase diagrams.
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Affiliation(s)
| | | | - Leon A Avakyan
- Southern Federal University, Rostov-on-Don, Russian Federation
| | - Valeriy M Talanov
- South-Russian State Polytechnic University, Novocherkassk, Russian Federation
| | - Khisa Sh Borlakov
- North Caucasian State Humanitarian and Technological Academy, Cherkessk, Russian Federation
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11
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Guo Y, Deng H, Sun X, Li X, Zhao J, Wu J, Chu W, Zhang S, Pan H, Zheng X, Wu X, Jin C, Wu C, Xie Y. Modulation of Metal and Insulator States in 2D Ferromagnetic VS 2 by van der Waals Interaction Engineering. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2017; 29:1700715. [PMID: 28585239 DOI: 10.1002/adma.201700715] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Revised: 04/21/2017] [Indexed: 06/07/2023]
Abstract
2D transition-metal dichalcogenides (TMDCs) are currently the key to the development of nanoelectronics. However, TMDCs are predominantly nonmagnetic, greatly hindering the advancement of their spintronic applications. Here, an experimental realization of intrinsic magnetic ordering in a pristine TMDC lattice is reported, bringing a new class of ferromagnetic semiconductors among TMDCs. Through van der Waals (vdW) interaction engineering of 2D vanadium disulfide (VS2 ), dual regulation of spin properties and bandgap brings about intrinsic ferromagnetism along with a small bandgap, unravelling the decisive role of vdW gaps in determining the electronic states in 2D VS2 . An overall control of the electronic states of VS2 is also demonstrated: bond-enlarging triggering a metal-to-semiconductor electronic transition and bond-compression inducing metallization in 2D VS2 . The pristine VS2 lattice thus provides a new platform for precise manipulation of both charge and spin degrees of freedom in 2D TMDCs availing spintronic applications.
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Affiliation(s)
- Yuqiao Guo
- Hefei National Laboratory for Physical Sciences at the Microscale, and, iChEM (Collaborative Innovation Centre of Chemistry for Energy Materials), University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China
| | - Haitao Deng
- Hefei National Laboratory for Physical Sciences at the Microscale, and, iChEM (Collaborative Innovation Centre of Chemistry for Energy Materials), University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China
| | - Xu Sun
- Hefei National Laboratory for Physical Sciences at the Microscale, and, iChEM (Collaborative Innovation Centre of Chemistry for Energy Materials), University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China
| | - Xiuling Li
- CAS Key Laboratory of Materials for Energy Conversion, School of Chemistry and Materials Sciences, and, CAS Center for Excellence in Nanoscience, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Jiyin Zhao
- Hefei National Laboratory for Physical Sciences at the Microscale, and, iChEM (Collaborative Innovation Centre of Chemistry for Energy Materials), University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China
| | - Junchi Wu
- Hefei National Laboratory for Physical Sciences at the Microscale, and, iChEM (Collaborative Innovation Centre of Chemistry for Energy Materials), University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China
| | - Wangsheng Chu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui, 230029, P. R. China
| | - Sijia Zhang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Collaborative Innovation Center of Quantum Matter, Beijing, 100190, China
| | - Haibin Pan
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui, 230029, P. R. China
| | - Xusheng Zheng
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui, 230029, P. R. China
| | - Xiaojun Wu
- CAS Key Laboratory of Materials for Energy Conversion, School of Chemistry and Materials Sciences, and, CAS Center for Excellence in Nanoscience, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Changqing Jin
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Collaborative Innovation Center of Quantum Matter, Beijing, 100190, China
| | - Changzheng Wu
- Hefei National Laboratory for Physical Sciences at the Microscale, and, iChEM (Collaborative Innovation Centre of Chemistry for Energy Materials), University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China
| | - Yi Xie
- Hefei National Laboratory for Physical Sciences at the Microscale, and, iChEM (Collaborative Innovation Centre of Chemistry for Energy Materials), University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China
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Murakami T, Yamamoto T, Tassel C, Takatsu H, Ritter C, Ajiro Y, Kageyama H. HfMnSb2 : A Metal-Ordered NiAs-type Pnictide with a Conical Spin Order. Angew Chem Int Ed Engl 2016; 55:9877-80. [PMID: 27355989 DOI: 10.1002/anie.201602066] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 05/08/2016] [Indexed: 11/07/2022]
Abstract
The NiAs-type structure is one of the most common structures in solids, but metal order has been almost exclusively limited to chalcogenides. The synthesis of HfMnSb2 is reported with a novel metal-ordered NiAs-type structure. HfMnSb2 undergoes a conical spin order below 270 K, in marked contrast to conventional magnetic order observed in NiAs-type pnictides. We argue that the layered arrangement of Hf and Mn makes it a quasi 2D magnet, where the Mn layers with localized magnetic moments (Mn(2+) ; S=5/2) can interact only through RKKY interactions, instead of metal-metal bonding that is otherwise dominant for typical NiAs-type pnictides. This result suggests that controlling order-disorder in NiAs-type pnictides enables a study of 2D-to-3D crossover behavior in itinerant magnetic system.
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Affiliation(s)
- Taito Murakami
- Graduate School of Engineering, Kyoto University, Kyoto, 615-8510, Japan
| | - Takafumi Yamamoto
- Graduate School of Engineering, Kyoto University, Kyoto, 615-8510, Japan
| | - Cédric Tassel
- Graduate School of Engineering, Kyoto University, Kyoto, 615-8510, Japan
| | - Hiroshi Takatsu
- Graduate School of Engineering, Kyoto University, Kyoto, 615-8510, Japan
| | - Clemens Ritter
- Institut Laue-Langevin, 6, rue Jules Horowitz, Grenoble, 38000, France
| | - Yoshitami Ajiro
- Graduate School of Engineering, Kyoto University, Kyoto, 615-8510, Japan
| | - Hiroshi Kageyama
- Graduate School of Engineering, Kyoto University, Kyoto, 615-8510, Japan.
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13
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Murakami T, Yamamoto T, Tassel C, Takatsu H, Ritter C, Ajiro Y, Kageyama H. HfMnSb
2
: A Metal‐Ordered NiAs‐type Pnictide with a Conical Spin Order. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201602066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Taito Murakami
- Graduate School of Engineering Kyoto University Kyoto 615-8510 Japan
| | - Takafumi Yamamoto
- Graduate School of Engineering Kyoto University Kyoto 615-8510 Japan
| | - Cédric Tassel
- Graduate School of Engineering Kyoto University Kyoto 615-8510 Japan
| | - Hiroshi Takatsu
- Graduate School of Engineering Kyoto University Kyoto 615-8510 Japan
| | - Clemens Ritter
- Institut Laue-Langevin 6, rue Jules Horowitz Grenoble 38000 France
| | - Yoshitami Ajiro
- Graduate School of Engineering Kyoto University Kyoto 615-8510 Japan
| | - Hiroshi Kageyama
- Graduate School of Engineering Kyoto University Kyoto 615-8510 Japan
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14
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Kobayashi S, Ueda H, Michioka C, Yoshimura K. Competition between the Direct Exchange Interaction and Superexchange Interaction in Layered Compounds LiCrSe2, LiCrTe2, and NaCrTe2 with a Triangular Lattice. Inorg Chem 2016; 55:7407-13. [PMID: 27400024 DOI: 10.1021/acs.inorgchem.6b00610] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Physical properties of new S = 3/2 triangular-lattice compounds LiCrSe2, LiCrTe2, and NaCrTe2 have been investigated by X-ray diffraction and magnetic measurements. These compounds crystallize in the ordered NiAs-type structure, where alkali metal ions and Cr atoms stack alternately. Despite their isomorphic structures, magnetic properties of these three compounds are different; NaCrTe2 has an A-type spin structure with ferromagnetic layers, LiCrTe2 is likely to exhibit a helical spin structure, and LiCrSe2 shows a first-order-like phase transition from the paramagnetic trigonal phase to the antiferromagnetic monoclinic phase. In these compounds and the other chromium chalcogenides with a triangular lattice, we found a general relationship between the Curie-Weiss temperature and magnetic structures. This relation indicates that the competition between the antiferromagnetic direct d-d exchange interaction and the ferromagnetic superexchange interaction plays an important role in determining the ground state of chromium chalcogenides.
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Affiliation(s)
- Shintaro Kobayashi
- Department of Chemistry, Graduate School of Science, Kyoto University , Kyoto 606-8502, Japan
| | - Hiroaki Ueda
- Department of Chemistry, Graduate School of Science, Kyoto University , Kyoto 606-8502, Japan
| | - Chishiro Michioka
- Department of Chemistry, Graduate School of Science, Kyoto University , Kyoto 606-8502, Japan
| | - Kazuyoshi Yoshimura
- Department of Chemistry, Graduate School of Science, Kyoto University , Kyoto 606-8502, Japan.,Research Center for Low Temperature and Materials Sciences, Kyoto University , Kyoto 606-8501, Japan
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15
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Talanov MV, Shirokov VB, Talanov VM. Phenomenological thermodynamics and the structure formation mechanism of the CuTi₂S₄ rhombohedral phase. Phys Chem Chem Phys 2016; 18:10600-6. [PMID: 27035866 DOI: 10.1039/c6cp00387g] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The theory of structural phase transition in CuTi2S4 is proposed. The symmetry of order parameters, thermodynamics and the mechanism of the atomic structure formation of the rhombohedral Cu-Ti-thiospinel have been studied. The critical order parameter inducing the phase transition has been found. Within the Landau theory of phase transitions, it is shown that the phase state may change from the high-symmetry cubic disordered Fd3[combining macron]m phase to the low-symmetry ordered rhombohedral R3[combining macron]m phase as a result of phase transition of the first order close to the second order. It is shown that the rhombohedral structure of CuTi2S4 is formed as a result of the displacements of all types of atoms and the ordering of Cu-atoms (1 : 1 order type in tetrahedral spinel sites), Ti-atoms (1 : 1 : 6 order type in octahedral spinel sites), and S-atoms (1 : 1 : 3 : 3 order type). The Cu- and Ti-atoms form metal nanoclusters which are named a "bunch" of dimers. The "bunch" of dimers in CuTi2S4 is a new type of self-organization of atoms in frustrated spinel-like structures. It is shown that Ti-atoms also form other types of metal nanoclusters: trimers and tetrahedra.
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16
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Hiroi Z. Structural instability of the rutile compounds and its relevance to the metal–insulator transition of VO2. PROG SOLID STATE CH 2015. [DOI: 10.1016/j.progsolidstchem.2015.02.001] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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17
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Sun X, Yao T, Hu Z, Guo Y, Liu Q, Wei S, Wu C. In situ unravelling structural modulation across the charge-density-wave transition in vanadium disulfide. Phys Chem Chem Phys 2015; 17:13333-9. [DOI: 10.1039/c5cp01326g] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Local structural evolution and electrical property variation in VS2 were analyzed via in situ X-ray absorption fine structure measurement and theoretical calculations.
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Affiliation(s)
- Xu Sun
- Hefei National Laboratory for Physical Sciences at the Microscale and iChEM (Collaborative Innovation Center of Chemistry for Energy Materials)
- University of Science and Technology of China
- Hefei 230026
- P. R. China
| | - Tao Yao
- National Synchrotron Radiation Laboratory
- University of Science and Technology of China
- Hefei
- P. R. China
| | - Zhenpeng Hu
- School of Physics
- Nankai University
- Tianjin
- P. R. China
| | - Yuqiao Guo
- Hefei National Laboratory for Physical Sciences at the Microscale and iChEM (Collaborative Innovation Center of Chemistry for Energy Materials)
- University of Science and Technology of China
- Hefei 230026
- P. R. China
| | - Qinghua Liu
- National Synchrotron Radiation Laboratory
- University of Science and Technology of China
- Hefei
- P. R. China
| | - Shiqiang Wei
- National Synchrotron Radiation Laboratory
- University of Science and Technology of China
- Hefei
- P. R. China
| | - Changzheng Wu
- Hefei National Laboratory for Physical Sciences at the Microscale and iChEM (Collaborative Innovation Center of Chemistry for Energy Materials)
- University of Science and Technology of China
- Hefei 230026
- P. R. China
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18
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Eom MJ, Kim K, Jo YJ, Yang JJ, Choi ES, Min BI, Park JH, Cheong SW, Kim JS. Dimerization-induced Fermi-surface reconstruction in IrTe2. PHYSICAL REVIEW LETTERS 2014; 113:266406. [PMID: 25615364 DOI: 10.1103/physrevlett.113.266406] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Indexed: 06/04/2023]
Abstract
We report a de Haas-van Alphen (dHvA) oscillation study on IrTe2 single crystals showing complex dimer formations. By comparing the angle dependence of dHvA oscillations with band structure calculations, we show distinct Fermi surface reconstruction induced by a 1/5-type and a 1/8-type dimerizations. This verifies that an intriguing quasi-two-dimensional conducting plane across the layers is induced by dimerization in both cases. A phase transition to the 1/8 phase with higher dimer density reveals that local instabilities associated with intra- and interdimer couplings are the main driving force for complex dimer formations in IrTe2.
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Affiliation(s)
- Man Jin Eom
- Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Korea
| | - Kyoo Kim
- Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Korea
| | - Y J Jo
- Department of Physics, Kyungpook National University, Daegu 702-701, Korea
| | - J J Yang
- Laboratory for Pohang Emergent Materials, Pohang University of Science and Technology, Pohang 790-784, Korea and Max Plank POSTECH Center for Complex Phase Materials, Pohang University of Science and Technology, Pohang 790-784, Korea
| | - E S Choi
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, USA
| | - B I Min
- Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Korea
| | - J-H Park
- Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Korea and Max Plank POSTECH Center for Complex Phase Materials, Pohang University of Science and Technology, Pohang 790-784, Korea
| | - S-W Cheong
- Laboratory for Pohang Emergent Materials, Pohang University of Science and Technology, Pohang 790-784, Korea and Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Piscataway, New Jersey 08854, USA
| | - Jun Sung Kim
- Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Korea
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19
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Klein Y, Moutaabbid H, Boubiche N, Soyer A, Rousse G, Gauzzi A. Weak localization and Mott state in two-dimensional Sr3V5S11. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:435604. [PMID: 24100229 DOI: 10.1088/0953-8984/25/43/435604] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We report on the high-pressure synthesis, structural study and physical properties of a new layered compound, Sr3V5S11. Single-crystals of ~0.3 mm size were synthesized at the optimized growth conditions of 6 GPa and 1600 ° C. The refinement of x-ray diffraction data indicates that the crystal structure is monoclinic (space group C2/c), with cell parameters a = 8.7165(7) Å, b = 15.1096(13) Å, c = 23.111(2) Å, and β = 98.734(9). The structure consists of a stacking of VS2 layers with a CdI2-type structure within the ab-plane connected by trimers of face-sharing VS6 octahedra oriented along the out-of-plane direction. Salient features are a 4 + valence of the V ions in the planes and a 3 + valence in the trimers and a large stripe-like modulation of the V-V distances in the planes leading to quasi-one-dimensional properties. The magnetic susceptibility displays a large temperature-independent contribution, χ0, in addition to a moderate Curie-Weiss term. In the 300-120 K range, the electrical resistivity is described well by a semiconducting-like behaviour with a room-temperature value of ~1.2-10 mΩ cm and a modest activation energy of ~13.5 meV. At lower temperatures, a crossover to a one-dimensional variable range hopping regime is observed, supporting a scenario of a correlated 1D system.
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Affiliation(s)
- Y Klein
- Institut de Minéralogie et de Physique des Milieux Condensés (IMPMC), CNRS UMR 7590, Université Pierre et Marie Curie (UPMC), 4 Place Jussieu, 75252 Paris Cedex 05, France
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20
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Ali MN, Ji H, Hirai D, Fuccillo M, Cava R. Synthesis and characterization of two crystallographic forms of Ag0.79VS2. J SOLID STATE CHEM 2013. [DOI: 10.1016/j.jssc.2013.03.038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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21
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Feng J, Sun X, Wu C, Peng L, Lin C, Hu S, Yang J, Xie Y. Metallic Few-Layered VS2 Ultrathin Nanosheets: High Two-Dimensional Conductivity for In-Plane Supercapacitors. J Am Chem Soc 2011; 133:17832-8. [DOI: 10.1021/ja207176c] [Citation(s) in RCA: 917] [Impact Index Per Article: 70.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Jun Feng
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science & Technology of China, Hefei, Anhui, 230026, P.R. China
| | - Xu Sun
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science & Technology of China, Hefei, Anhui, 230026, P.R. China
| | - Changzheng Wu
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science & Technology of China, Hefei, Anhui, 230026, P.R. China
| | - Lele Peng
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science & Technology of China, Hefei, Anhui, 230026, P.R. China
| | - Chenwen Lin
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science & Technology of China, Hefei, Anhui, 230026, P.R. China
| | - Shuanglin Hu
- Shanghai Supercomputer Center, Shanghai, 201203, P.R. China
| | - Jinlong Yang
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science & Technology of China, Hefei, Anhui, 230026, P.R. China
| | - Yi Xie
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science & Technology of China, Hefei, Anhui, 230026, P.R. China
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22
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Khomskii DI. Novel electronic states close to Mott transition in low-dimensional and frustrated systems. ACTA ACUST UNITED AC 2011. [DOI: 10.1088/1742-6596/320/1/012055] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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23
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Wilson JA. A perspective on the Fe-based superconductors. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:203201. [PMID: 21393700 DOI: 10.1088/0953-8984/22/20/203201] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
FeSe is employed as reference material to elucidate the observed high T(c) superconducting behaviour of the related layered iron pnictides. The structural and ensuing semimetallic band structural forms are here rather unusual, with the resulting ground state details extremely sensitive to the precise shape of the Fe-X coordination unit. The superconductivity is presented as coming from a combination of resonant valence bond and excitonic insulator physics, and incorporating boson-fermion degeneracy. Although sourced in a very different fashion, the latter leads to some similarities with the high temperature superconducting (HTSC) cuprates. The excitonic insulator behaviour sees spin density wave, charge density wave/periodic structural distortion, and superconductive instabilities all vie for ground state status. The conflict leads to a very sensitive and complex set of properties, frequently mirroring HTSC cuprate behaviour. The delicate balance between ground states is made particularly difficult to unravel by the micro-inhomogeneity of structural form which it can engender. It is pointed out that several other notable superconductors, layered in form, semimetallic with indirect overlap and possessing homopolar bonding, would look to fall into the same general category, β-ZrNCl and MgB(2) and the high pressure forms of several elements, like sulfur, phosphorus, lithium and calcium, being cases in point.
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Affiliation(s)
- John A Wilson
- H H Wills Physics Laboratory, University of Bristol, Bristol BS8 1TL, UK.
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Miyazaki J, Matsudaira K, Shimizu Y, Itoh M, Nagamine Y, Mori S, Kim JE, Kato K, Takata M, Katsufuji T. Formation of a three-dimensional network of V trimers in A2V13O22 (A=Ba, Sr). PHYSICAL REVIEW LETTERS 2010; 104:207201. [PMID: 20867054 DOI: 10.1103/physrevlett.104.207201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Indexed: 05/29/2023]
Abstract
We found that in A2V13O22 (A=Ba, Sr), which contains a trilayer slab of VO in the sodium-chloride structure with periodically missing ions, the trimerization of V ions occurs at 290 K (A=Ba) and 380 K (A=Sr). V trimers form a three-dimensional network, but some V ions remain untrimerized in these compounds. The suppression of magnetic susceptibility with trimerization and the existence of a Curie tail at low temperatures, together with the result of NMR measurement, indicate that the V trimers are spin singlet, whereas the untrimerized V ions have a magnetic moment; i.e., there is a spontaneous separation between nonmagnetic and magnetic ions in the crystal.
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Affiliation(s)
- J Miyazaki
- Department of Physics, Waseda University, Tokyo 169-8555, Japan
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