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Zhang L, Wang Y, Hu R, Wan P, Zheliuk O, Liang M, Peng X, Zeng YJ, Ye J. Correlated States in Strained Twisted Bilayer Graphenes Away from the Magic Angle. Nano Lett 2022; 22:3204-3211. [PMID: 35385281 PMCID: PMC9052762 DOI: 10.1021/acs.nanolett.1c04400] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Graphene moiré superlattice formed by rotating two graphene sheets can host strongly correlated and topological states when flat bands form at so-called magic angles. Here, we report that, for a twisting angle far away from the magic angle, the heterostrain induced during stacking heterostructures can also create flat bands. Combining a direct visualization of strain effect in twisted bilayer graphene moiré superlattices and transport measurements, features of correlated states appear at "non-magic" angles in twisted bilayer graphene under the heterostrain. Observing correlated states in these "non-standard" conditions can enrich the understanding of the possible origins of the correlated states and widen the freedom in tuning the moiré heterostructures and the scope of exploring the correlated physics in moiré superlattices.
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Affiliation(s)
- Le Zhang
- College
of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
- Device
Physics of Complex Materials, Zernike Institute for Advanced Materials, University of Groningen, 9747AG Groningen, The Netherlands
| | - Ying Wang
- Device
Physics of Complex Materials, Zernike Institute for Advanced Materials, University of Groningen, 9747AG Groningen, The Netherlands
| | - Rendong Hu
- Device
Physics of Complex Materials, Zernike Institute for Advanced Materials, University of Groningen, 9747AG Groningen, The Netherlands
| | - Puhua Wan
- Device
Physics of Complex Materials, Zernike Institute for Advanced Materials, University of Groningen, 9747AG Groningen, The Netherlands
| | - Oleksandr Zheliuk
- Device
Physics of Complex Materials, Zernike Institute for Advanced Materials, University of Groningen, 9747AG Groningen, The Netherlands
- CogniGron
(Groningen Cognitive Systems and Materials Center), University of Groningen, 9747AG Groningen, The Netherlands
| | - Minpeng Liang
- Device
Physics of Complex Materials, Zernike Institute for Advanced Materials, University of Groningen, 9747AG Groningen, The Netherlands
| | - Xiaoli Peng
- Device
Physics of Complex Materials, Zernike Institute for Advanced Materials, University of Groningen, 9747AG Groningen, The Netherlands
| | - Yu-Jia Zeng
- College
of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
| | - Jianting Ye
- Device
Physics of Complex Materials, Zernike Institute for Advanced Materials, University of Groningen, 9747AG Groningen, The Netherlands
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2
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Tay D, Shang T, Qi YP, Ying TP, Hosono H, Ott HR, Shiroka T. s-wave superconductivity in the noncentrosymmetric W 3Al 2C superconductor: an NMR study. J Phys Condens Matter 2022; 34:194005. [PMID: 35193132 DOI: 10.1088/1361-648x/ac577a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 02/22/2022] [Indexed: 06/14/2023]
Abstract
We report on a microscopic study of the noncentrosymmetric superconductor W3Al2C (withTc= 7.6 K), mostly by means of27Al- and13C nuclear magnetic resonance (NMR). Since in this material the density of states at the Fermi level is dominated by the tungsten's 5dorbitals, we expect a sizeable spin-orbit coupling (SOC) effect. The normal-state electronic properties of W3Al2C resemble those of a standard metal, but with a Korringa product 1/(T1T) significantly smaller than that of metallic Al, reflecting the marginal role played bys-electrons. In the superconducting state, we observe a reduction of the Knight shift and an exponential decrease of the NMR relaxation rate 1/T1, typical ofs-wave superconductivity (SC). This is further supported by the observation of a small but distinct coherence peak just belowTcin the13C NMR relaxation-rate, in agreement with the fully-gapped superconducting state inferred from the electronic specific-heat data well belowTc. The above features are compared to those of members of the same family, in particular, Mo3Al2C, often claimed to exhibit unconventional SC. We discuss why, despite the enhanced SOC, W3Al2C does not show spin-triplet features in its superconducting state and consider the broader consequences of our results for noncentrosymmetric superconductors in general.
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Affiliation(s)
- D Tay
- Laboratorium für Festkörperphysik, ETH Zürich, CH-8093 Zurich, Switzerland
| | - T Shang
- Key Laboratory of Polar Materials and Devices (MOE), School of Physics and Electronic Science, East China Normal University, Shanghai 200241, People's Republic of China
| | - Y P Qi
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, People's Republic of China
| | - T P Ying
- Materials Research Center for Element Strategy, Tokyo Institute of Technology, Yokohama 226-8503, Japan
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - H Hosono
- Materials Research Center for Element Strategy, Tokyo Institute of Technology, Yokohama 226-8503, Japan
| | - H-R Ott
- Laboratorium für Festkörperphysik, ETH Zürich, CH-8093 Zurich, Switzerland
- Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - T Shiroka
- Laboratorium für Festkörperphysik, ETH Zürich, CH-8093 Zurich, Switzerland
- Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
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3
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Chen G, Sharpe AL, Fox EJ, Wang S, Lyu B, Jiang L, Li H, Watanabe K, Taniguchi T, Crommie MF, Kastner MA, Shi Z, Goldhaber-Gordon D, Zhang Y, Wang F. Tunable Orbital Ferromagnetism at Noninteger Filling of a Moiré Superlattice. Nano Lett 2022; 22:238-245. [PMID: 34978444 DOI: 10.1021/acs.nanolett.1c03699] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The flat bands resulting from moiré superlattices exhibit fascinating correlated electron phenomena such as correlated insulators, ( Nature 2018, 556 (7699), 80-84), ( Nature Physics 2019, 15 (3), 237) superconductivity, ( Nature 2018, 556 (7699), 43-50), ( Nature 2019, 572 (7768), 215-219) and orbital magnetism. ( Science 2019, 365 (6453), 605-608), ( Nature 2020, 579 (7797), 56-61), ( Science 2020, 367 (6480), 900-903) Such magnetism has been observed only at particular integer multiples of n0, the density corresponding to one electron per moiré superlattice unit cell. Here, we report the experimental observation of ferromagnetism at noninteger filling (NIF) of a flat Chern band in a ABC-TLG/hBN moiré superlattice. This state exhibits prominent ferromagnetic hysteresis behavior with large anomalous Hall resistivity in a broad region of densities centered in the valence miniband at n = -2.3n0. We observe that, not only the magnitude of the anomalous Hall signal, but also the sign of the hysteretic ferromagnetic response can be modulated by tuning the carrier density and displacement field. Rotating the sample in a fixed magnetic field demonstrates that the ferromagnetism is highly anisotropic and likely purely orbital in character.
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Affiliation(s)
- Guorui Chen
- Department of Physics, University of California at Berkeley, Berkeley, California 94720, United States
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Aaron L Sharpe
- Department of Applied Physics, Stanford University, Stanford, California 94305, United States
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
- Quantum and Electronic Materials Department, Sandia National Laboratories, Livermore, California 94550, United States
| | - Eli J Fox
- Department of Applied Physics, Stanford University, Stanford, California 94305, United States
- Department of Physics, Stanford University, Stanford, California 94305, United States
| | - Shaoxin Wang
- Department of Physics, University of California at Berkeley, Berkeley, California 94720, United States
| | - Bosai Lyu
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Lili Jiang
- Department of Physics, University of California at Berkeley, Berkeley, California 94720, United States
| | - Hongyuan Li
- Department of Physics, University of California at Berkeley, Berkeley, California 94720, United States
- Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Michael F Crommie
- Department of Physics, University of California at Berkeley, Berkeley, California 94720, United States
- Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Kavli Energy NanoSciences Institute, University of California, Berkeley and the Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Marc A Kastner
- Department of Applied Physics, Stanford University, Stanford, California 94305, United States
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
- Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Zhiwen Shi
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
| | - David Goldhaber-Gordon
- Department of Applied Physics, Stanford University, Stanford, California 94305, United States
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Yuanbo Zhang
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
- Institute for Nanoelectronic Devices and Quantum Computing, Fudan University, Shanghai 200433, China
| | - Feng Wang
- Department of Physics, University of California at Berkeley, Berkeley, California 94720, United States
- Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Kavli Energy NanoSciences Institute, University of California, Berkeley and the Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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Dhawan R, Balasubramanian P, Nautiyal T. Structural, electronic and magnetic properties of weakly correlated metal Sr 2CrTiO 6: a first principles study. J Phys Condens Matter 2021; 34:055501. [PMID: 34700313 DOI: 10.1088/1361-648x/ac334f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 10/26/2021] [Indexed: 06/13/2023]
Abstract
Structural, electronic and magnetic behaviour of a less-explored material Sr2CrTiO6has been investigated usingabinitiocalculations with generalized gradient approximation (GGA) and GGA +Umethods, whereUis the Hubbard parameter. For each of the three possible Cr/Ti cationic arrangements in the unit cell, considered in this work, the non-magnetic band structure shows distinct traits with significant flat-band regions leading to larget2gdensity of states around the Fermi energy. The Cr4+ion in Sr2CrTiO6, which is ad2system, shows a reverse splitting of thet2gorbitals. The calculated hopping matrix contains non-zero off-diagonal elements between thedxzanddyzorbitals, while thedxyorbitals remain largely unmixed. A minimal tight binding model successfully reproduces the sixt2gbands around the Fermi energy. The Fermi surface shows a two-dimensional nesting feature for the layered arrangement of Cr and Ti atoms. Fixed spin moment studies suggest that the magnetism in this compound cannot be explained by Stoner's criterion of an itinerant band ferromagnet. In the absence of HubbardUterm, the ground state is a half-metallic ferromagnet. Calculations for the anti-ferromagnetic spin arrangement show re-arrangement of orbital character resulting in (a) narrowdxz/dyzbands and sharp peaks in the density of states at the Fermi energy and (b) highly dispersivedxybands with a broader density of states around the Fermi energy. The metallicity persists even with increasingUfor both the spin arrangements, thus suggesting that Sr2CrTiO6belongs to the class of weakly correlated metals, while the shifting of O 2pstates towards the Fermi energy withUindicates a negative charge-transfer character in Sr2CrTiO6.
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Affiliation(s)
- Rakshanda Dhawan
- Department of Physics, Indian Institute of technology, Roorkee-247667, Uttarakhand, India
| | | | - Tashi Nautiyal
- Department of Physics, Indian Institute of technology, Roorkee-247667, Uttarakhand, India
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5
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Sharpe AL, Fox EJ, Barnard AW, Finney J, Watanabe K, Taniguchi T, Kastner MA, Goldhaber-Gordon D. Evidence of Orbital Ferromagnetism in Twisted Bilayer Graphene Aligned to Hexagonal Boron Nitride. Nano Lett 2021; 21:4299-4304. [PMID: 33970644 DOI: 10.1021/acs.nanolett.1c00696] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
We have previously reported ferromagnetism evinced by a large hysteretic anomalous Hall effect in twisted bilayer graphene (tBLG). Subsequent measurements of a quantized Hall resistance and small longitudinal resistance confirmed that this magnetic state is a Chern insulator. Here, we report that when tilting the sample in an external magnetic field, the ferromagnetism is highly anisotropic. Because spin-orbit coupling is weak in graphene, such anisotropy is unlikely to come from spin but rather favors theories in which the ferromagnetism is orbital. We know of no other case in which ferromagnetism has a purely orbital origin. For an applied in-plane field larger than 5 T, the out-of-plane magnetization is destroyed, suggesting a transition to a new phase.
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Affiliation(s)
- Aaron L Sharpe
- Department of Applied Physics, Stanford University, 348 Via Pueblo Mall, Stanford, California 94305, United States
- Stanford Institute for Materials and Energy Science, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States
| | - Eli J Fox
- Stanford Institute for Materials and Energy Science, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States
- Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305, United States
| | - Arthur W Barnard
- Stanford Institute for Materials and Energy Science, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States
- Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305, United States
- Department of Physics and Department of Materials Science and Engineering, University of Washington, 302 Roberts Hall, Seattle, Washington 98195, United States
| | - Joe Finney
- Stanford Institute for Materials and Energy Science, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States
- Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305, United States
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Marc A Kastner
- Stanford Institute for Materials and Energy Science, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States
- Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305, United States
- Department of Physics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - David Goldhaber-Gordon
- Stanford Institute for Materials and Energy Science, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States
- Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305, United States
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6
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Lukoyanov AV, Gramateeva LN, Knyazev YV, Kuz’min YI, Gupta S, Suresh KG. Effect of Electronic Correlations on the Electronic Structure, Magnetic and Optical Properties of the Ternary RCuGe Compounds with R = Tb, Dy, Ho, Er. Materials (Basel) 2020; 13:ma13163536. [PMID: 32796558 PMCID: PMC7475831 DOI: 10.3390/ma13163536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 08/07/2020] [Accepted: 08/09/2020] [Indexed: 06/11/2023]
Abstract
In this study, the ab initio and experimental results for RCuGe ternary intermetallics were reported for R = Tb, Dy, Ho, Er. Our theoretical calculations of the electronic structure, employing local spin density approximation accounting for electron-electron correlations in the 4f shell of Tb, Dy, Ho, Er ions were carried in DFT+U method. The optical properties of the RCuGe ternary compounds were studied at a broad range of wavelengths. The spectral and electronic characteristics were obtained. The theoretical electron densities of states were taken to interpret the experimental energy dependencies of the experimental optical conductivity in the interband light-absorption region. From the band calculations, the 4f shell of the rare-earth ions was shown to provide the major contribution to the electronic structure, magnetic and optical properties of the RCuGe intermetallics. The accounting for electron-electron correlations in Tb, Dy, Ho, Er resulted in a good agreement between the calculated and experimental magnetic and optical characteristics.
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Affiliation(s)
- Alexey V. Lukoyanov
- M.N. Miheev Institute of Metal Physics of Ural Branch of Russian Academy of Sciences, 620108 Ekaterinburg, Russia; (L.N.G.); (Y.V.K.); (Y.I.K.)
- Ural Federal University named after the first President of Russia B.N. Yeltsin, 620002 Ekaterinburg, Russia
| | - Lubov N. Gramateeva
- M.N. Miheev Institute of Metal Physics of Ural Branch of Russian Academy of Sciences, 620108 Ekaterinburg, Russia; (L.N.G.); (Y.V.K.); (Y.I.K.)
| | - Yury V. Knyazev
- M.N. Miheev Institute of Metal Physics of Ural Branch of Russian Academy of Sciences, 620108 Ekaterinburg, Russia; (L.N.G.); (Y.V.K.); (Y.I.K.)
| | - Yury I. Kuz’min
- M.N. Miheev Institute of Metal Physics of Ural Branch of Russian Academy of Sciences, 620108 Ekaterinburg, Russia; (L.N.G.); (Y.V.K.); (Y.I.K.)
| | - Sachin Gupta
- Department of Electronic Science and Engineering, Kyoto University, Kyoto 615-8510, Japan;
- Department of Physics, Indian Institute of Technology Bombay, Mumbai 400076, India;
| | - K. G. Suresh
- Department of Physics, Indian Institute of Technology Bombay, Mumbai 400076, India;
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7
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Abstract
Finite graphene nanoribbon (GNR) heterostructures host intriguing topological in-gap states (Rizzo, D. J.; et al. Nature2018, 560, 204). These states may be localized either at the bulk edges or at the ends of the structure. Here we show that correlation effects (not included in previous density functional simulations) play a key role in these systems: they result in increased magnetic moments at the ribbon edges accompanied by a significant energy renormalization of the topological end states, even in the presence of a metallic substrate. Our computed results are in excellent agreement with the experiments. Furthermore, we discover a striking, novel mechanism that causes an energy splitting of the nonzero-energy topological end states for a weakly screened system. We predict that similar effects should be observable in other GNR heterostructures as well.
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Affiliation(s)
- Jan-Philip Joost
- Institut für Theoretische Physik und Astrophysik , Christian-Albrechts-Universität zu Kiel , D-24098 Kiel , Germany
| | - Antti-Pekka Jauho
- CNG, DTU Physics , Technical University of Denmark , Kongens Lyngby , DK 2800 , Denmark
| | - Michael Bonitz
- Institut für Theoretische Physik und Astrophysik , Christian-Albrechts-Universität zu Kiel , D-24098 Kiel , Germany
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8
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Xinmao Yin, Ming Yang, Chi Sin Tang, Qixing Wang, Lei Xu, Jing Wu, Paolo Emilio Trevisanutto, Shengwei Zeng, Xin Yu Chin, Teguh Citra Asmara, Yuan Ping Feng, Ariando Ariando, Manish Chhowalla, Shi Jie Wang, Wenjing Zhang, Andrivo Rusydi, Andrew T. S. Wee. Excitons: Modulation of New Excitons in Transition Metal Dichalcogenide‐Perovskite Oxide System (Adv. Sci. 12/2019). Adv Sci (Weinh) 2019; 6:1970073. [ DOI: 10.1002/advs.201970073] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
In article number 1900446, Shi Jie Wang, Wenjing Zhang, Andrivo Rusydi, Andrew T. S. Wee, and co‐workers observe high‐energy excitons that are generated by a new mechanism in monolayer‐MoS2 on SrTiO3, which are attributed to the change in many‐body interactions that couples with interfacial orbital‐hybridization. The interfacial interactions lead to a fermi‐surface feature at the interface. The results provide an understanding of 2D‐transition metal dichalcogenides heterointerfaces and show the crucial role that many‐body interactions play at the atomic level.
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Yin X, Yang M, Tang CS, Wang Q, Xu L, Wu J, Trevisanutto PE, Zeng S, Chin XY, Asmara TC, Feng YP, Ariando A, Chhowalla M, Wang SJ, Zhang W, Rusydi A, Wee ATS. Modulation of New Excitons in Transition Metal Dichalcogenide-Perovskite Oxide System. Adv Sci (Weinh) 2019; 6:1900446. [PMID: 31380174 PMCID: PMC6662271 DOI: 10.1002/advs.201900446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 03/31/2019] [Indexed: 06/10/2023]
Abstract
The exciton, a quasi-particle that creates a bound state of an electron and a hole, is typically found in semiconductors. It has attracted major attention in the context of both fundamental science and practical applications. Transition metal dichalcogenides (TMDs) are a new class of 2D materials that include direct band-gap semiconductors with strong spin-orbit coupling and many-body interactions. Manipulating new excitons in semiconducting TMDs could generate a novel means of application in nanodevices. Here, the observation of high-energy excitonic peaks in the monolayer-MoS2 on a SrTiO3 heterointerface generated by a new complex mechanism is reported, based on a comprehensive study that comprises temperature-dependent optical spectroscopies and first-principles calculations. The appearance of these excitons is attributed to the change in many-body interactions that occurs alongside the interfacial orbital hybridization and spin-orbit coupling brought about by the excitonic effect propagated from the substrate. This has further led to the formation of a Fermi-surface feature at the interface. The results provide an atomic-scale understanding of the heterointerface between monolayer-TMDs and perovskite oxide and highlight the importance of spin-orbit-charge-lattice coupling on the intrinsic properties of atomic-layer heterostructures, which open up a way to manipulate the excitonic effects in monolayer TMDs via an interfacial system.
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Affiliation(s)
- Xinmao Yin
- International Collaborative Laboratory of 2D Materials for Optoelectronics Science and TechnologyShenzhen UniversityShenzhen518060China
- Department of PhysicsFaculty of ScienceNational University of SingaporeSingapore117542Singapore
- Singapore Synchrotron Light Source (SSLS)National University of SingaporeSingapore117603Singapore
| | - Ming Yang
- Institute of Materials Research and EngineeringA∗STAR (Agency for Science, Technology and Research)2 Fusionopolis WaySingapore138634Singapore
| | - Chi Sin Tang
- Department of PhysicsFaculty of ScienceNational University of SingaporeSingapore117542Singapore
- NUS Graduate School for Integrative Sciences and EngineeringNational University of SingaporeSingapore117456Singapore
| | - Qixing Wang
- Department of PhysicsFaculty of ScienceNational University of SingaporeSingapore117542Singapore
| | - Lei Xu
- Department of PhysicsFaculty of ScienceNational University of SingaporeSingapore117542Singapore
| | - Jing Wu
- Institute of Materials Research and EngineeringA∗STAR (Agency for Science, Technology and Research)2 Fusionopolis WaySingapore138634Singapore
| | - Paolo Emilio Trevisanutto
- Centre for Advanced 2D Materials and Graphene Research CentreNational University of SingaporeSingapore117551Singapore
| | - Shengwei Zeng
- Department of PhysicsFaculty of ScienceNational University of SingaporeSingapore117542Singapore
- NUSNNI‐NanoCoreNational University of SingaporeSingapore117576Singapore
| | - Xin Yu Chin
- Energy Research Institute @ NTU (ERI@N)Research Techno PlazaX‐Frontier Block, Level 5, 50 Nanyang DriveSingapore637553Singapore
| | - Teguh Citra Asmara
- Department of PhysicsFaculty of ScienceNational University of SingaporeSingapore117542Singapore
- Singapore Synchrotron Light Source (SSLS)National University of SingaporeSingapore117603Singapore
| | - Yuan Ping Feng
- Department of PhysicsFaculty of ScienceNational University of SingaporeSingapore117542Singapore
- Centre for Advanced 2D Materials and Graphene Research CentreNational University of SingaporeSingapore117551Singapore
| | - Ariando Ariando
- Department of PhysicsFaculty of ScienceNational University of SingaporeSingapore117542Singapore
- NUS Graduate School for Integrative Sciences and EngineeringNational University of SingaporeSingapore117456Singapore
- NUSNNI‐NanoCoreNational University of SingaporeSingapore117576Singapore
| | - Manish Chhowalla
- Department of Materials Science and MetallurgyUniversity of CambridgeCambridgeCB30FSUK
| | - Shi Jie Wang
- Department of PhysicsFaculty of ScienceNational University of SingaporeSingapore117542Singapore
- Institute of Materials Research and EngineeringA∗STAR (Agency for Science, Technology and Research)2 Fusionopolis WaySingapore138634Singapore
| | - Wenjing Zhang
- International Collaborative Laboratory of 2D Materials for Optoelectronics Science and TechnologyShenzhen UniversityShenzhen518060China
| | - Andrivo Rusydi
- Department of PhysicsFaculty of ScienceNational University of SingaporeSingapore117542Singapore
- Singapore Synchrotron Light Source (SSLS)National University of SingaporeSingapore117603Singapore
- NUS Graduate School for Integrative Sciences and EngineeringNational University of SingaporeSingapore117456Singapore
- NUSNNI‐NanoCoreNational University of SingaporeSingapore117576Singapore
| | - Andrew T. S. Wee
- Department of PhysicsFaculty of ScienceNational University of SingaporeSingapore117542Singapore
- Singapore Synchrotron Light Source (SSLS)National University of SingaporeSingapore117603Singapore
- NUS Graduate School for Integrative Sciences and EngineeringNational University of SingaporeSingapore117456Singapore
- Centre for Advanced 2D Materials and Graphene Research CentreNational University of SingaporeSingapore117551Singapore
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10
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Anisimov VI, Lukoyanov AV. Investigation of real materials with strong electronic correlations by the LDA+DMFT method. Acta Crystallogr C Struct Chem 2014; 70:137-59. [PMID: 24508959 DOI: 10.1107/s2053229613032312] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 11/20/2013] [Indexed: 11/10/2022] Open
Abstract
Materials with strong electronic correlations are at the cutting edge of experimental and theoretical studies, capturing the attention of researchers for a great variety of interesting phenomena: metal-insulator, phase and magnetic spin transitions, `heavy fermion' systems, interplay between magnetic order and superconductivity, appearance and disappearance of local magnetic moments, and transport property anomalies. It is clear that the richness of physical phenomena for these compounds is a result of partially filled 3d, 4f or 5f electron shells with local magnetic moments preserved in the solid state. Strong interactions of d and f electrons with each other and with itinerant electronic states of the material are responsible for its anomalous properties. Electronic structure calculations for strongly correlated materials should explicitly take into account Coulombic interactions between d or f electrons. Recent advances in this field are related to the development of the LDA+DMFT method, which combines local density approximation (LDA) with dynamical mean-field theory (DMFT) to account for electronic correlation effects. In recent years, LDA+DMFT has allowed the successful treatment not only of simple systems but also of complicated real compounds. Nowadays, the LDA+DMFT method is the state-of-the-art tool for investigating correlated metals and insulators, spin and metal-insulator transitions (MIT) in transition-metal compounds in paramagnetic and magnetically ordered phases.
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Affiliation(s)
- V I Anisimov
- Institute of Metal Physics, Russian Academy of Sciences, 620990 Yekaterinburg, Russia
| | - A V Lukoyanov
- Institute of Metal Physics, Russian Academy of Sciences, 620990 Yekaterinburg, Russia
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