1
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Mo S, Seo J, Son SK, Kim S, Rhim JW, Lee H. Engineering Two-Dimensional Nodal Semimetals in Functionalized Biphenylene by Fluorine Adatoms. NANO LETTERS 2024; 24. [PMID: 38607382 PMCID: PMC11057037 DOI: 10.1021/acs.nanolett.4c00314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2024] [Revised: 04/10/2024] [Accepted: 04/10/2024] [Indexed: 04/13/2024]
Abstract
We propose a band engineering scheme on the biphenylene network, a newly synthesized carbon allotrope. We illustrate that the electronic structure of the biphenylene network can be significantly altered by controlling conditions affecting the symmetry and destructive interference of wave functions through periodic fluorination. First, we investigate the mechanism for the appearance of a type-II Dirac fermion in a pristine biphenylene network. We show that the essential ingredients are mirror symmetries and stabilization of the compact localized eigenstates via destructive interference. While the former is used for the band-crossing point along high symmetry lines, the latter induces highly inclined Dirac dispersions. Subsequently, we demonstrate the transformation of the biphenylene network's type-II Dirac semimetal phase into various Dirac phases such as type-I Dirac, gapped type-II Dirac, and nodal line semimetals through the deliberate disruption of mirror symmetry or modulation of destructive interference by varying the concentration of fluorine atoms.
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Affiliation(s)
- Seongjun Mo
- Department
of Physics, Konkuk University, Seoul 05029, Korea
| | - Jaeuk Seo
- Department
of Physics, Ajou University, Suwon 16499, Korea
- Department
of Physics, Korea Advanced Institute of
Science and Technology, Daejeon 34141, Korea
| | - Seok-Kyun Son
- Department
of Physics, Kyung Hee University, Seoul 02447, Republic of Korea
- Department
of Information Display, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Sejoong Kim
- University
of Science and Technology (UST), Gajeong-ro 217, Daejeon 34113, Korea
- Korea
Institute for Advanced Study, Hoegiro 85, Seoul 02455, Korea
| | - Jun-Won Rhim
- Research
Center for Novel Epitaxial Quantum Architectures, Department of Physics, Seoul National University, Seoul 08826, Korea
- Department
of Physics, Ajou University, Suwon 16499, Korea
| | - Hoonkyung Lee
- Department
of Physics, Konkuk University, Seoul 05029, Korea
- Research
Center for Novel Epitaxial Quantum Architectures, Department of Physics, Seoul National University, Seoul 08826, Korea
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2
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Kitamura T, Daido A, Yanase Y. Spin-Triplet Superconductivity from Quantum-Geometry-Induced Ferromagnetic Fluctuation. PHYSICAL REVIEW LETTERS 2024; 132:036001. [PMID: 38307086 DOI: 10.1103/physrevlett.132.036001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 11/19/2023] [Accepted: 11/29/2023] [Indexed: 02/04/2024]
Abstract
We show that quantum geometry induces ferromagnetic fluctuation resulting in spin-triplet superconductivity. The criterion for ferromagnetic fluctuation is clarified by analyzing contributions from the effective mass and quantum geometry. When the non-Kramers band degeneracy is present near the Fermi surface, the Fubini-Study quantum metric strongly favors ferromagnetic fluctuation. Solving the linearized gap equation with the effective interaction obtained by the random phase approximation, we show that the spin-triplet superconductivity is mediated by quantum-geometry-induced ferromagnetic fluctuation.
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Affiliation(s)
- Taisei Kitamura
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Akito Daido
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Youichi Yanase
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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3
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Yu HM, Sharma S, Agarwal S, Liebman O, Banerjee AS. Carbon Kagome nanotubes-quasi-one-dimensional nanostructures with flat bands. RSC Adv 2024; 14:963-981. [PMID: 38188261 PMCID: PMC10768532 DOI: 10.1039/d3ra06988e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2023] [Accepted: 11/29/2023] [Indexed: 01/09/2024] Open
Abstract
In recent years, a number of bulk materials and heterostructures have been explored due their connections with exotic materials phenomena emanating from flat band physics and strong electronic correlation. The possibility of realizing such fascinating material properties in simple realistic nanostructures is particularly exciting, especially as the investigation of exotic states of electronic matter in wire-like geometries is relatively unexplored in the literature. Motivated by these considerations, we introduce in this work carbon Kagome nanotubes (CKNTs)-a new allotrope of carbon formed by rolling up Kagome graphene, and investigate this material using specialized first principles calculations. We identify two principal varieties of CKNTs-armchair and zigzag, and find both varieties to be stable at room temperature, based on ab initio molecular dynamics simulations. CKNTs are metallic and feature dispersionless states (i.e., flat bands) near the Fermi level throughout their Brillouin zone, along with an associated singular peak in the electronic density of states. We calculate the mechanical and electronic response of CKNTs to torsional and axial strains, and show that CKNTs appear to be more mechanically compliant than conventional carbon nanotubes (CNTs). Additionally, we find that the electronic properties of CKNTs undergo significant electronic transitions-with emergent partial flat bands and tilted Dirac points-when twisted. We develop a relatively simple tight-binding model that can explain many of these electronic features. We also discuss possible routes for the synthesis of CKNTs. Overall, CKNTs appear to be unique and striking examples of realistic elemental quasi-one-dimensional materials that may display fascinating material properties due to strong electronic correlation. Distorted CKNTs may provide an interesting nanomaterial platform where flat band physics and chirality induced anomalous transport effects may be studied together.
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Affiliation(s)
- Husan Ming Yu
- Department of Materials Science and Engineering, University of California Los Angeles CA 90095 USA +1-763-656-7830
| | - Shivam Sharma
- Department of Aerospace Engineering and Mechanics, University of Minnesota Minneapolis MN 55455 USA
| | - Shivang Agarwal
- Department of Electrical and Computer Engineering, University of California Los Angeles CA 90095 USA
| | - Olivia Liebman
- Department of Materials Science and Engineering, University of California Los Angeles CA 90095 USA +1-763-656-7830
| | - Amartya S Banerjee
- Department of Materials Science and Engineering, University of California Los Angeles CA 90095 USA +1-763-656-7830
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4
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Chen Y, Huang J, Jiang K, Hu J. Decoding flat bands from compact localized states. Sci Bull (Beijing) 2023; 68:3165-3171. [PMID: 38007328 DOI: 10.1016/j.scib.2023.11.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 09/11/2023] [Accepted: 11/03/2023] [Indexed: 11/27/2023]
Abstract
The flat band system is an ideal quantum platform to investigate the kaleidoscope created by the electron-electron correlation effects. The central ingredient of realizing a flat band is to find its compact localized states. In this work, we develop a systematic way to generate compact localized states by designing destructive interference patterns from 1-dimensional chains. A variety of 2-dimensional new flat band systems are constructed with this method. Furthermore, we show that the method can be extended to generate the compact localized states in multi-orbital systems by carefully designing the block hopping scheme, as well as in quasicrystal and disorder systems.
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Affiliation(s)
- Yuge Chen
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Juntao Huang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China; School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Kun Jiang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China; School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China.
| | - Jiangping Hu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China; Kavli Institute of Theoretical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China.
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5
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Song L, Gao S, Ma J, Tang L, Song D, Li Y, Chen Z. Multiple flatbands and localized states in photonic super-Kagome lattices. OPTICS LETTERS 2023; 48:5947-5950. [PMID: 37966759 DOI: 10.1364/ol.504794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Accepted: 10/14/2023] [Indexed: 11/16/2023]
Abstract
We demonstrate multiple flatbands and compact localized states (CLSs) in a photonic super-Kagome lattice (SKL) that exhibits coexistence of singular and nonsingular flatbands within its unique band structure. Specifically, we find that the upper two flatbands of an SKL are singular-characterized by singularities due to band touching with their neighboring dispersive bands at the Brillouin zone center. Conversely, the lower three degenerate flatbands are nonsingular and remain spectrally isolated from other dispersive bands. The existence of such two distinct types of flatbands is experimentally demonstrated by observing stable evolution of the CLSs with various geometrical shapes in a laser-written SKL. We also discuss the classification of the flatbands in momentum space, using band-touching singularities of the Bloch wave functions. Furthermore, we validate this classification in real space based on unit cell occupancy of the CLSs in a single SKL plaquette. These results may provide insights for the study of flatband transport, dynamics, and nontrivial topological phenomena in other relevant systems.
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6
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Zhang X, He T, Liu Y, Dai X, Liu G, Chen C, Wu W, Zhu J, Yang SA. Magnetic Real Chern Insulator in 2D Metal-Organic Frameworks. NANO LETTERS 2023; 23:7358-7363. [PMID: 37535707 DOI: 10.1021/acs.nanolett.3c01723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/05/2023]
Abstract
Real Chern insulators have attracted great interest, but so far, their material realization is limited to nonmagnetic crystals and systems without spin-orbit coupling. Here, we reveal the magnetic real Chern insulator (MRCI) state in a recently synthesized metal-organic framework material Co3(HITP)2. Its ground state with in-plane ferromagnetic ordering hosts a nontrivial real Chern number, enabled by the C2zT symmetry and robustness against spin-orbit coupling. Distinct from previous nonmagnetic examples, the topological corner zero modes of MRCIs are spin-polarized. Furthermore, under small tensile strains, the material undergoes a topological phase transition from the MRCI to a magnetic double-Weyl semimetal phase, via a pseudospin-1 critical state. Similar physics can also be found in closely related materials Mn3(HITP)2 and Fe3(HITP)2, which also exist. Possible experimental detections and implications of an emerging magnetic flat band in the system are discussed.
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Affiliation(s)
- Xiaoming Zhang
- State Key Laboratory of Reliability and Intelligence of Electrical Equipment, Hebei University of Technology, Tianjin 300130, China
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, China
| | - Tingli He
- State Key Laboratory of Reliability and Intelligence of Electrical Equipment, Hebei University of Technology, Tianjin 300130, China
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, China
| | - Ying Liu
- State Key Laboratory of Reliability and Intelligence of Electrical Equipment, Hebei University of Technology, Tianjin 300130, China
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, China
| | - Xuefang Dai
- State Key Laboratory of Reliability and Intelligence of Electrical Equipment, Hebei University of Technology, Tianjin 300130, China
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, China
| | - Guodong Liu
- State Key Laboratory of Reliability and Intelligence of Electrical Equipment, Hebei University of Technology, Tianjin 300130, China
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, China
| | - Cong Chen
- Department of Physics, The University of Hong Kong, Hong Kong, China
- HKU-UCAS Joint Institute of Theoretical and Computational Physics at Hong Kong, Hong Kong, China
| | - Weikang Wu
- Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), Shandong University, Jinan 250061, China
| | - Jiaojiao Zhu
- Research Laboratory for Quantum Materials, Singapore University of Technology and Design, Singapore 487372, Singapore
| | - Shengyuan A Yang
- Research Laboratory for Quantum Materials, Singapore University of Technology and Design, Singapore 487372, Singapore
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7
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Jin KH, Jiang W, Sethi G, Liu F. Topological quantum devices: a review. NANOSCALE 2023; 15:12787-12817. [PMID: 37490310 DOI: 10.1039/d3nr01288c] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/26/2023]
Abstract
The introduction of the concept of topology into condensed matter physics has greatly deepened our fundamental understanding of transport properties of electrons as well as all other forms of quasi particles in solid materials. It has also fostered a paradigm shift from conventional electronic/optoelectronic devices to novel quantum devices based on topology-enabled quantum device functionalities that transfer energy and information with unprecedented precision, robustness, and efficiency. In this article, the recent research progress in topological quantum devices is reviewed. We first outline the topological spintronic devices underlined by the spin-momentum locking property of topology. We then highlight the topological electronic devices based on quantized electron and dissipationless spin conductivity protected by topology. Finally, we discuss quantum optoelectronic devices with topology-redefined photoexcitation and emission. The field of topological quantum devices is only in its infancy, we envision many significant advances in the near future.
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Affiliation(s)
- Kyung-Hwan Jin
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), Pohang 37673, Republic of Korea
| | - Wei Jiang
- School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Gurjyot Sethi
- Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, USA.
| | - Feng Liu
- Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, USA.
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8
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Gao A, Liu YF, Qiu JX, Ghosh B, V Trevisan T, Onishi Y, Hu C, Qian T, Tien HJ, Chen SW, Huang M, Bérubé D, Li H, Tzschaschel C, Dinh T, Sun Z, Ho SC, Lien SW, Singh B, Watanabe K, Taniguchi T, Bell DC, Lin H, Chang TR, Du CR, Bansil A, Fu L, Ni N, Orth PP, Ma Q, Xu SY. Quantum metric nonlinear Hall effect in a topological antiferromagnetic heterostructure. Science 2023:eadf1506. [PMID: 37319246 DOI: 10.1126/science.adf1506] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 06/06/2023] [Indexed: 06/17/2023]
Abstract
Quantum geometry in condensed matter physics has two components: the real part quantum metric and the imaginary part Berry curvature. Whereas the effects of Berry curvature have been observed through phenomena such as the quantum Hall effect in 2D electron gases and the anomalous Hall effect (AHE) in ferromagnets, quantum metric has rarely been explored. Here, we report a nonlinear Hall effect induced by quantum metric dipole by interfacing even-layered MnBi2Te4 with black phosphorus. The quantum metric nonlinear Hall effect switches direction upon reversing the AFM spins and exhibits distinct scaling that is independent of the scattering time. Our results open the door to discovering quantum metric responses predicted theoretically and pave the way for applications that bridge nonlinear electronics with AFM spintronics.
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Affiliation(s)
- Anyuan Gao
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Yu-Fei Liu
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
| | - Jian-Xiang Qiu
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Barun Ghosh
- Department of Physics, Northeastern University, Boston, MA 02115, USA
| | - Thaís V Trevisan
- Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA
- Ames National Laboratory, Ames, IA 50011, USA
| | - Yugo Onishi
- Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Chaowei Hu
- Department of Physics and Astronomy and California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Tiema Qian
- Department of Physics and Astronomy and California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Hung-Ju Tien
- Department of Physics, National Cheng Kung University, Tainan 701, Taiwan
| | - Shao-Wen Chen
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
| | - Mengqi Huang
- Department of Physics, University of California San Diego, La Jolla, CA 92093, USA
| | - Damien Bérubé
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Houchen Li
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Christian Tzschaschel
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Thao Dinh
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
| | - Zhe Sun
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
- Department of Physics, Boston College, Chestnut Hill, MA, USA
| | - Sheng-Chin Ho
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Shang-Wei Lien
- Department of Physics, National Cheng Kung University, Tainan 701, Taiwan
| | - Bahadur Singh
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Colaba, Mumbai, India
| | - Kenji Watanabe
- International Center for Materials Nanoarchitectonics, 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
| | - David C Bell
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
- Center for Nanoscale Systems, Harvard University, Cambridge, MA 02138, USA
| | - Hsin Lin
- Institute of Physics, Academia Sinica, Taipei 11529, Taiwan
| | - Tay-Rong Chang
- Department of Physics, National Cheng Kung University, Tainan 701, Taiwan
| | - Chunhui Rita Du
- Department of Physics, University of California San Diego, La Jolla, CA 92093, USA
| | - Arun Bansil
- Department of Physics, Northeastern University, Boston, MA 02115, USA
| | - Liang Fu
- Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ni Ni
- Department of Physics and Astronomy and California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Peter P Orth
- Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA
- Ames National Laboratory, Ames, IA 50011, USA
| | - Qiong Ma
- Department of Physics, Boston College, Chestnut Hill, MA, USA
| | - Su-Yang Xu
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
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9
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Jiang K, Wu T, Yin JX, Wang Z, Hasan MZ, Wilson SD, Chen X, Hu J. Kagome superconductors AV 3Sb 5 (A = K, Rb, Cs). Natl Sci Rev 2023; 10:nwac199. [PMID: 36935933 PMCID: PMC10016199 DOI: 10.1093/nsr/nwac199] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 01/20/2022] [Accepted: 02/14/2022] [Indexed: 11/14/2022] Open
Abstract
The quasi-two-dimensional kagome materials AV3Sb5 (A = K, Rb, Cs) were found to be a prime example of kagome superconductors, a new quantum platform to investigate the interplay between electron correlation effects, topology and geometric frustration. In this review, we report recent progress on the experimental and theoretical studies of AV3Sb5 and provide a broad picture of this fast-developing field in order to stimulate an expanded search for unconventional kagome superconductors. We review the electronic properties of AV3Sb5, the experimental measurements of the charge density wave state, evidence of time-reversal symmetry breaking and other potential hidden symmetry breaking in these materials. A variety of theoretical proposals and models that address the nature of the time-reversal symmetry breaking are discussed. Finally, we review the superconducting properties of AV3Sb5, especially the potential pairing symmetries and the interplay between superconductivity and the charge density wave state.
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Affiliation(s)
- Kun Jiang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Tao Wu
- Corresponding author. E-mail:
| | | | - Zhenyu Wang
- CAS Key Laboratory of Strongly-coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei 230026, China
| | - M Zahid Hasan
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ 08544, USA
| | - Stephen D Wilson
- Materials Department and California Nanosystems Institute, University of California Santa Barbara, Santa Barbara, CA 93106, USA
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10
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Viñas Boström E, Parvini TS, McIver JW, Rubio A, Kusminskiy SV, Sentef MA. Direct Optical Probe of Magnon Topology in Two-Dimensional Quantum Magnets. PHYSICAL REVIEW LETTERS 2023; 130:026701. [PMID: 36706407 DOI: 10.1103/physrevlett.130.026701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 12/12/2022] [Indexed: 06/18/2023]
Abstract
Controlling edge states of topological magnon insulators is a promising route to stable spintronics devices. However, to experimentally ascertain the topology of magnon bands is a challenging task. Here we derive a fundamental relation between the light-matter coupling and the quantum geometry of magnon states. This allows us to establish the two-magnon Raman circular dichroism as an optical probe of magnon topology in honeycomb magnets, in particular of the Chern number and the topological gap. Our results pave the way for interfacing light and topological magnons in functional quantum devices.
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Affiliation(s)
- Emil Viñas Boström
- Max Planck Institute for the Structure and Dynamics of Matter, Center for Free Electron Laser Science (CFEL), Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Tahereh Sadat Parvini
- Institute of Physics, University of Greifswald, Felix-Hausdorff-Strasse 6, Greifswald, 17489, Germany
| | - James W McIver
- Max Planck Institute for the Structure and Dynamics of Matter, Center for Free Electron Laser Science (CFEL), Luruper Chaussee 149, 22761 Hamburg, Germany
- Department of Physics, Columbia University, New York, New York 10027, USA
| | - Angel Rubio
- Max Planck Institute for the Structure and Dynamics of Matter, Center for Free Electron Laser Science (CFEL), Luruper Chaussee 149, 22761 Hamburg, Germany
- Center for Computational Quantum Physics, The Flatiron Institute, 162 Fifth Avenue, New York, New York 10010, USA
| | - Silvia Viola Kusminskiy
- Institute for Theoretical Solid State Physics, RWTH Aachen University, 52074 Aachen, Germany
- Max Planck Institute for the Science of Light, Staudtstrasse 2, PLZ 91058 Erlangen, Germany
| | - Michael A Sentef
- Max Planck Institute for the Structure and Dynamics of Matter, Center for Free Electron Laser Science (CFEL), Luruper Chaussee 149, 22761 Hamburg, Germany
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11
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Arora A, Rudner MS, Song JCW. Quantum Plasmonic Nonreciprocity in Parity-Violating Magnets. NANO LETTERS 2022; 22:9351-9357. [PMID: 36383645 DOI: 10.1021/acs.nanolett.2c03126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The optical responses of metals are often dominated by plasmonic resonances, that is, the collective oscillations of interacting electron liquids. Here we unveil a new class of plasmons─quantum metric plasmons (QMPs)─that arise in a wide range of parity-violating magnetic metals. In these materials, a dipolar distribution of the quantum metric (a fundamental characteristic of Bloch wave functions) produces intrinsic nonreciprocal bulk plasmons. Strikingly, QMP nonreciprocity manifests even when the single-particle dispersion is symmetric: QMPs are sensitive to time-reversal and parity violations hidden in the Bloch wave function. In materials with asymmetric single-particle dispersions, quantum metric dipole induced nonreciprocity can continue to dominate at large frequencies. We anticipate that QMPs can be realized in a wide range of parity-violating magnets, including twisted bilayer graphene heterostructures, where quantum geometric quantities can achieve large values.
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Affiliation(s)
- Arpit Arora
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore637371
| | - Mark S Rudner
- Department of Physics, University of Washington, SeattleWashington98195, United States
| | - Justin C W Song
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore637371
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12
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Abstract
A kagome lattice naturally features Dirac fermions, flat bands and van Hove singularities in its electronic structure. The Dirac fermions encode topology, flat bands favour correlated phenomena such as magnetism, and van Hove singularities can lead to instabilities towards long-range many-body orders, altogether allowing for the realization and discovery of a series of topological kagome magnets and superconductors with exotic properties. Recent progress in exploring kagome materials has revealed rich emergent phenomena resulting from the quantum interactions between geometry, topology, spin and correlation. Here we review these key developments in this field, starting from the fundamental concepts of a kagome lattice, to the realizations of Chern and Weyl topological magnetism, to various flat-band many-body correlations, and then to the puzzles of unconventional charge-density waves and superconductivity. We highlight the connection between theoretical ideas and experimental observations, and the bond between quantum interactions within kagome magnets and kagome superconductors, as well as their relation to the concepts in topological insulators, topological superconductors, Weyl semimetals and high-temperature superconductors. These developments broadly bridge topological quantum physics and correlated many-body physics in a wide range of bulk materials and substantially advance the frontier of topological quantum matter.
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13
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Brown CD, Chang SW, Schwarz MN, Leung TH, Kozii V, Avdoshkin A, Moore JE, Stamper-Kurn D. Direct geometric probe of singularities in band structure. Science 2022; 377:1319-1322. [DOI: 10.1126/science.abm6442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
A quantum system’s energy landscape may have points where multiple energy surfaces are degenerate and that exhibit singular geometry of the wave function manifold, with major consequences for the system’s properties. Ultracold atoms in optical lattices have been used to indirectly characterize such points in the band structure. We measured the non-Abelian transformation produced by transport directly through the singularities. We accelerated atoms along a quasi-momentum trajectory that enters, turns, and then exits the singularities at linear and quadratic band-touching points of a honeycomb lattice. Measurements after transport identified the topological winding numbers of these singularities to be 1 and 2, respectively. Our work introduces a distinct method for probing singularities that enables the study of non-Dirac singularities in ultracold-atom quantum simulators.
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Affiliation(s)
- Charles D. Brown
- Department of Physics, University of California, Berkeley, Berkeley, CA 94720, USA
- Challenge Institute for Quantum Computation, University of California, Berkeley, Berkeley, CA 94720, USA
- Department of Physics, Yale University, New Haven, CT 06520, USA
| | - Shao-Wen Chang
- Department of Physics, University of California, Berkeley, Berkeley, CA 94720, USA
- Challenge Institute for Quantum Computation, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Malte N. Schwarz
- Department of Physics, University of California, Berkeley, Berkeley, CA 94720, USA
- Challenge Institute for Quantum Computation, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Tsz-Him Leung
- Department of Physics, University of California, Berkeley, Berkeley, CA 94720, USA
- Challenge Institute for Quantum Computation, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Vladyslav Kozii
- Department of Physics, University of California, Berkeley, Berkeley, CA 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Alexander Avdoshkin
- Department of Physics, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Joel E. Moore
- Department of Physics, University of California, Berkeley, Berkeley, CA 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Dan Stamper-Kurn
- Department of Physics, University of California, Berkeley, Berkeley, CA 94720, USA
- Challenge Institute for Quantum Computation, University of California, Berkeley, Berkeley, CA 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
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14
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Chu Y, Cai J. Thermodynamic Principle for Quantum Metrology. PHYSICAL REVIEW LETTERS 2022; 128:200501. [PMID: 35657873 DOI: 10.1103/physrevlett.128.200501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 04/28/2022] [Indexed: 06/15/2023]
Abstract
The heat dissipation in quantum metrology represents not only an unavoidable problem towards practical applications of quantum sensing devices but also a fundamental relationship between thermodynamics and quantum metrology. However, a general thermodynamic principle which governs the rule of energy consumption in quantum metrology, similar to Landauer's principle for heat dissipation in computations, has remained elusive. Here, we establish such a physical principle for energy consumption in order to achieve a certain level of measurement precision in quantum metrology, and show that it is intrinsically determined by the erasure of quantum Fisher information. The principle provides a powerful tool to investigate the advantage of quantum resources, not only in measurement precision but also in energy efficiency. It also serves as a bridge between thermodynamics and various fundamental physical concepts related in quantum physics and quantum information theory.
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Affiliation(s)
- Yaoming Chu
- School of Physics, Hubei Key Laboratory of Gravitation and Quantum Physics, Institute for Quantum Science and Engineering, International Joint Laboratory on Quantum Sensing and Quantum Metrology, Huazhong University of Science and Technology, Wuhan 430074, China and Wuhan National High Magnetic Field Center, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Jianming Cai
- School of Physics, Hubei Key Laboratory of Gravitation and Quantum Physics, Institute for Quantum Science and Engineering, International Joint Laboratory on Quantum Sensing and Quantum Metrology, Huazhong University of Science and Technology, Wuhan 430074, China and Wuhan National High Magnetic Field Center, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China
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15
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Catalogue of flat-band stoichiometric materials. Nature 2022; 603:824-828. [PMID: 35355002 DOI: 10.1038/s41586-022-04519-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 02/04/2022] [Indexed: 11/08/2022]
Abstract
Topological electronic flattened bands near or at the Fermi level are a promising route towards unconventional superconductivity and correlated insulating states. However, the related experiments are mostly limited to engineered materials, such as moiré systems1-3. Here we present a catalogue of the naturally occuring three-dimensional stoichiometric materials with flat bands around the Fermi level. We consider 55,206 materials from the Inorganic Crystal Structure Database catalogued using the Topological Quantum Chemistry website4,5, which provides their structural parameters, space group, band structure, density of states and topological characterization. We combine several direct signatures and properties of band flatness with a high-throughput analysis of all crystal structures. In particular, we identify materials hosting line-graph or bipartite sublattices-in either two or three dimensions-that probably lead to flat bands. From this trove of information, we create the Materials Flatband Database website, a powerful search engine for future theoretical and experimental studies. We use the database to extract a curated list of 2,379 high-quality flat-band materials, from which we identify 345 promising candidates that potentially host flat bands with charge centres that are not strongly localized on the atomic sites. We showcase five representative materials and provide a theoretical explanation for the origin of their flat bands close to the Fermi energy using the S-matrix method introduced in a parallel work6.
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16
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Ni X, Li H, Liu F, Brédas JL. Engineering of flat bands and Dirac bands in two-dimensional covalent organic frameworks (COFs): relationships among molecular orbital symmetry, lattice symmetry, and electronic-structure characteristics. MATERIALS HORIZONS 2022; 9:88-98. [PMID: 34866138 DOI: 10.1039/d1mh00935d] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Two-dimensional covalent organic frameworks (2D-COFs), also referred to as 2D polymer networks, display unusual electronic-structure characteristics, which can significantly enrich and broaden the fields of electronics and spintronics. In this Focus article, our objective is to lay the groundwork for the conceptual description of the fundamental relationships among the COF electronic structures, the symmetries of their 2D lattices, and the frontier molecular orbitals (MOs) of their core and linker components. We focus on monolayers of hexagonal COFs and use tight-binding model analyses to highlight the critical role of the frontier-MO symmetry, in addition to lattice symmetry, in determining the nature of the electronic bands near the Fermi level. We rationalize the intriguing feature that, when the core unit has degenerate highest occupied MOs [or lowest unoccupied MOs], the COF highest valence band [or lowest conduction band] is flat but degenerate with a dispersive band at a high-symmetry point of the Brillouin zone; the consequences of having such band characteristics are briefly described. Multi-layer and bulk 2D COFs are found to maintain the salient features of the monolayer electronic structures albeit with a reduced bandgap due to the interlayer coupling. This Focus article is thus meant to provide an effective framework for the engineering of flat and Dirac bands in 2D polymer networks.
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Affiliation(s)
- Xiaojuan Ni
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona 85721-0088, USA.
| | - Hong Li
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona 85721-0088, USA.
| | - Feng Liu
- Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, USA
| | - Jean-Luc Brédas
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona 85721-0088, USA.
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17
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Lopes Lage L, Latge A. Electronic fractal patterns in building Sierpinski-triangles molecular systems. Phys Chem Chem Phys 2022; 24:19576-19583. [DOI: 10.1039/d2cp02426h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The Sierpinski Triangle (ST) is a fractal mathematical structure that has been used to explore the emergence of flat bands in lattices of different geometries and dimensions in condensed matter....
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18
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Xia S, Zhang Y, Li Z, Qin L, Yang C, Lu H, Zhang J, Zhao X, Zhu Z. Band evolution and Landau-Zener Bloch oscillations in strained photonic rhombic lattices. OPTICS EXPRESS 2021; 29:37503-37514. [PMID: 34808820 DOI: 10.1364/oe.441554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 10/19/2021] [Indexed: 06/13/2023]
Abstract
We investigate band evolution of chiral and non-chiral symmetric flatband photonic rhombic lattices by applying a strain along the diagonal direction, and thereby demonstrating Landau-Zener Bloch (LZB) oscillations in the presence of a refractive index gradient. The chiral and non-chiral symmetric rhombic lattices are obtained by adding a detuning to uniform lattices. For the chiral symmetric lattices, the middle flatband is perturbed due to the chiral symmetry breaking while a nearly flatband appears as the bottom band with the increase of strain-induced next-nearest-neighbor hopping. Consequently, LZB oscillations exhibit intriguing characteristics such as asymmetric energy transitions and almost complete suppression of the oscillations. Nevertheless, for the non-chiral symmetric lattices, flatband persists owing to the retained particle-hole symmetry and evolves into the bottom band. Remarkably, the band gap can be readily tuned, which allows controlling of the amplitude of Landau-Zener tunneling (LZT) rate and may lead to thorough LZT. Our analysis provides an alternative perspective on the generation of tunable flatband and may also bring insight to study the symmetry and topological characterization of the flatband.
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19
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Hwang Y, Rhim JW, Yang BJ. Geometric characterization of anomalous Landau levels of isolated flat bands. Nat Commun 2021; 12:6433. [PMID: 34741062 PMCID: PMC8571270 DOI: 10.1038/s41467-021-26765-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 10/14/2021] [Indexed: 12/03/2022] Open
Abstract
According to the Onsager’s semiclassical quantization rule, the Landau levels of a band are bounded by its upper and lower band edges at zero magnetic field. However, there are two notable systems where the Landau level spectra violate this expectation, including topological bands and flat bands with singular band crossings, whose wave functions possess some singularities. Here, we introduce a distinct class of flat band systems where anomalous Landau level spreading (LLS) appears outside the zero-field energy bounds, although the relevant wave function is nonsingular. The anomalous LLS of isolated flat bands are governed by the cross-gap Berry connection that measures the wave-function geometry of multi bands. We also find that symmetry puts strong constraints on the LLS of flat bands. Our work demonstrates that an isolated flat band is an ideal system for studying the fundamental role of wave-function geometry in describing magnetic responses of solids. Landau levels are normally bounded by upper and lower band edges at zero magnetic field. Here, the authors predict a system with isolated flat bands, where anomalous Landau level spreading appears outside the zero-field energy bounds.
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Affiliation(s)
- Yoonseok Hwang
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, 08826, Korea.,Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Korea.,Center for Theoretical Physics (CTP), Seoul National University, Seoul, 08826, Korea
| | - Jun-Won Rhim
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, 08826, Korea. .,Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Korea. .,Department of Physics, Ajou University, Suwon, 16499, Korea.
| | - Bohm-Jung Yang
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, 08826, Korea. .,Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Korea. .,Center for Theoretical Physics (CTP), Seoul National University, Seoul, 08826, Korea.
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20
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Román-Cortés D, Fadic G, Cid-Lara C, Guzmán-Silva D, Real B, Vicencio RA. Strain induced localization to delocalization transition on a Lieb photonic ribbon lattice. Sci Rep 2021; 11:21411. [PMID: 34725440 PMCID: PMC8560923 DOI: 10.1038/s41598-021-00967-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Accepted: 10/20/2021] [Indexed: 11/09/2022] Open
Abstract
Ribbon lattices are kind of transition systems in between one and two dimensions, and their study is crucial to understand the origin of different emerging properties. In this work, we study a Lieb ribbon lattice and the localization-delocalization transition occurring due to a reduction of lattice distances (compression) and the corresponding flat band deformation. We observe how above a critical compression ratio the energy spreads out and propagates freely across the lattice, therefore transforming the system from being a kind of insulator into a conductor. We implement an experiment on a photonic platform and show an excellent agreement with the predicted phenomenology. Our findings suggest and prove experimentally the use of compression or mechanical deformation of lattices to switch the transport properties of a given system.
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Affiliation(s)
- Diego Román-Cortés
- Departamento de Física and Millenium Institute for Research in Optics-MIRO, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Santiago, Chile
| | - Guillermo Fadic
- Departamento de Física and Millenium Institute for Research in Optics-MIRO, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Santiago, Chile
| | - Christofer Cid-Lara
- Departamento de Física and Millenium Institute for Research in Optics-MIRO, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Santiago, Chile
| | - Diego Guzmán-Silva
- Departamento de Física and Millenium Institute for Research in Optics-MIRO, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Santiago, Chile
| | - Bastián Real
- Univ. Lille, CNRS, UMR 8523-PhLAM-Physique des Lasers Atomes et Molécules, 59000, Lille, France
| | - Rodrigo A Vicencio
- Departamento de Física and Millenium Institute for Research in Optics-MIRO, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Santiago, Chile.
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21
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Julku A, Bruun GM, Törmä P. Quantum Geometry and Flat Band Bose-Einstein Condensation. PHYSICAL REVIEW LETTERS 2021; 127:170404. [PMID: 34739285 DOI: 10.1103/physrevlett.127.170404] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 09/24/2021] [Indexed: 06/13/2023]
Abstract
We study the properties of a weakly interacting Bose-Einstein condensate (BEC) in a flat band lattice system by using the multiband Bogoliubov theory and discover fundamental connections to the underlying quantum geometry. In a flat band, the speed of sound and the quantum depletion of the condensate are dictated by the quantum geometry, and a finite quantum distance between the condensed and other states guarantees stability of the BEC. Our results reveal that a suitable quantum geometry allows one to reach the strong quantum correlation regime even with weak interactions.
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Affiliation(s)
- Aleksi Julku
- Department of Applied Physics, Aalto University, P.O. Box 15100, 00076 Aalto, Finland
- Center for Complex Quantum Systems, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C, Denmark
| | - Georg M Bruun
- Center for Complex Quantum Systems, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C, Denmark
- Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Päivi Törmä
- Department of Applied Physics, Aalto University, P.O. Box 15100, 00076 Aalto, Finland
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22
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Wu Q, Liu J, Guan Y, Yazyev OV. Landau Levels as a Probe for Band Topology in Graphene Moiré Superlattices. PHYSICAL REVIEW LETTERS 2021; 126:056401. [PMID: 33605745 DOI: 10.1103/physrevlett.126.056401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 01/05/2021] [Indexed: 06/12/2023]
Abstract
We propose Landau levels as a probe for the topological character of electronic bands in two-dimensional moiré superlattices. We consider two configurations of twisted double bilayer graphene (TDBG) that have very similar band structures, but show different valley Chern numbers of the flat bands. These differences between the AB-AB and AB-BA configurations of TDBG clearly manifest as different Landau level sequences in the Hofstadter butterfly spectra calculated using the tight-binding model. The Landau level sequences are explained from the point of view of the distribution of orbital magnetization in momentum space that is governed by the rotational C_{2} and time-reversal T symmetries. Our results can be readily extended to other twisted graphene multilayers and h-BN/graphene heterostructures thus establishing the Hofstadter butterfly spectra as a powerful tool for detecting the nontrivial valley band topology.
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Affiliation(s)
- QuanSheng Wu
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- National Centre for Computational Design and Discovery of Novel Materials MARVEL, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Jianpeng Liu
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 200031, China
- ShanghaiTech Laboratory for Topological Physics, ShanghaiTech University, Shanghai 200031, China
| | - Yifei Guan
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Oleg V Yazyev
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- National Centre for Computational Design and Discovery of Novel Materials MARVEL, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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