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Qiu G, Yang HY, Chong SK, Cheng Y, Tai L, Wang KL. Manipulating Topological Phases in Magnetic Topological Insulators. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2655. [PMID: 37836296 PMCID: PMC10574534 DOI: 10.3390/nano13192655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 09/21/2023] [Accepted: 09/25/2023] [Indexed: 10/15/2023]
Abstract
Magnetic topological insulators (MTIs) are a group of materials that feature topological band structures with concurrent magnetism, which can offer new opportunities for technological advancements in various applications, such as spintronics and quantum computing. The combination of topology and magnetism introduces a rich spectrum of topological phases in MTIs, which can be controllably manipulated by tuning material parameters such as doping profiles, interfacial proximity effect, or external conditions such as pressure and electric field. In this paper, we first review the mainstream MTI material platforms where the quantum anomalous Hall effect can be achieved, along with other exotic topological phases in MTIs. We then focus on highlighting recent developments in modulating topological properties in MTI with finite-size limit, pressure, electric field, and magnetic proximity effect. The manipulation of topological phases in MTIs provides an exciting avenue for advancing both fundamental research and practical applications. As this field continues to develop, further investigations into the interplay between topology and magnetism in MTIs will undoubtedly pave the way for innovative breakthroughs in the fundamental understanding of topological physics as well as practical applications.
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Affiliation(s)
- Gang Qiu
- Department of Electrical and Computer Engineering, University of California, Los Angeles, CA 90095, USA; (H.-Y.Y.); (S.K.C.); (Y.C.); (L.T.)
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Hung-Yu Yang
- Department of Electrical and Computer Engineering, University of California, Los Angeles, CA 90095, USA; (H.-Y.Y.); (S.K.C.); (Y.C.); (L.T.)
| | - Su Kong Chong
- Department of Electrical and Computer Engineering, University of California, Los Angeles, CA 90095, USA; (H.-Y.Y.); (S.K.C.); (Y.C.); (L.T.)
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
| | - Yang Cheng
- Department of Electrical and Computer Engineering, University of California, Los Angeles, CA 90095, USA; (H.-Y.Y.); (S.K.C.); (Y.C.); (L.T.)
| | - Lixuan Tai
- Department of Electrical and Computer Engineering, University of California, Los Angeles, CA 90095, USA; (H.-Y.Y.); (S.K.C.); (Y.C.); (L.T.)
| | - Kang L. Wang
- Department of Electrical and Computer Engineering, University of California, Los Angeles, CA 90095, USA; (H.-Y.Y.); (S.K.C.); (Y.C.); (L.T.)
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2
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Sun K, Bao ZQ, Yu W, Hawkins SD, Klem JF, Pan W, Shi X. Charge transport spectra in superconductor-InAs/GaSb-superconductor heterostructures. NANOTECHNOLOGY 2021; 33:085703. [PMID: 34787108 DOI: 10.1088/1361-6528/ac3a36] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 11/15/2021] [Indexed: 06/13/2023]
Abstract
Charge transport physics in InAs/GaSb bi-layer systems has recently attracted attention for the experimental search for two-dimensional topological superconducting states in solids. Here we report measurement of charge transport spectra of nano devices consisting of an InAs/GaSb quantum well sandwiched by tantalum superconductors. We explore the current-voltage relation as a function of the charge-carrier density in the quantum well controlled by a gate voltage and an external magnetic field. We observe three types of differential resistance peaks, all of which can be effectively tuned by the external magnetic field, and, however, two of which appear at electric currents independent of the gate voltage, indicating a dominant mechanism from the superconductor and the system geometry. By analyzing the spectroscopic features, we find that the three types of peaks identify Andreev reflections, quasi-particle interference, and superconducting transitions in the device, respectively. Our results provide a basis for further exploration of possible topological superconducting state in the InAs/GaSb system.
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Affiliation(s)
- Kuei Sun
- Department of Physics, The University of Texas at Dallas, Richardson, TX 75080, United States of America
| | - Zhi-Qiang Bao
- Key Laboratory of Polar Materials and Devices (MOE), Department of Electronics, East China Normal University, Shanghai 200241, People's Republic of China
| | - Wenlong Yu
- Sandia National Laboratories, Albuquerque, NM 87185, United States of America
| | - Samuel D Hawkins
- Sandia National Laboratories, Albuquerque, NM 87185, United States of America
| | - John F Klem
- Sandia National Laboratories, Albuquerque, NM 87185, United States of America
| | - Wei Pan
- Sandia National Laboratories, Livermore, CA 94551, United States of America
| | - Xiaoyan Shi
- Department of Physics, The University of Texas at Dallas, Richardson, TX 75080, United States of America
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3
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Campos T, Toloza Sandoval MA, Diago-Cisneros L, Sipahi GM. Electrical tuning of helical edge states in topological multilayers. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:495501. [PMID: 31382252 DOI: 10.1088/1361-648x/ab38a1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Mainstream among topological insulators, GaSb/InAs quantum wells present a broken gap alignment for the energy bands which supports the quantum spin Hall insulator phase and forms an important building block in the search of exotic states of matter. Such structures allow the band-gap inversion with electrons and holes confined in adjacent layers, providing a fertile ground to tune the corresponding topological properties. Using a full 3D eight-band [Formula: see text] method we investigate the inverted band structure of GaSb/InAs/GaSb and InAs/GaSb/InAs multilayers and the behavior of the helical edge states, under the influence of an electric field applied along the growth direction. By tuning the electric field modulus, we induce the change of the energy levels of both conduction and valence bands, resulting in a quantum spin Hall insulator phase where the helical edge states are predominantly confined in the GaSb layer. In particular, we found that InAs/GaSb/InAs has a large hybridization gap of about [Formula: see text] and, therefore, are promising to observe massless Dirac fermions with a large Fermi velocity. Our comprehensive characterization of GaSb/InAs multilayers creates a basis platform upon which further optimization of III-V heterostructures can be contrasted.
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Affiliation(s)
- T Campos
- Department of Physics, State University of New York at Buffalo, Buffalo, NY 14260, United States of America. Instituto de Física de São Carlos, Universidade de São Paulo, São Carlos, São Paulo 13566-590, Brazil
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4
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Xiao D, Liu CX, Samarth N, Hu LH. Anomalous Quantum Oscillations of Interacting Electron-Hole Gases in Inverted Type-II InAs/GaSb Quantum Wells. PHYSICAL REVIEW LETTERS 2019; 122:186802. [PMID: 31144871 DOI: 10.1103/physrevlett.122.186802] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 04/10/2019] [Indexed: 06/09/2023]
Abstract
We report magnetotransport studies of InAs/GaSb bilayer quantum wells in a regime where the interlayer tunneling between the electron and hole gases is suppressed. When the chemical potential is tuned close to the charge neutrality point, we observe anomalous quantum oscillations that are inversely periodic in magnetic field and that have an extremely high frequency despite the highly insulating regime where they are observed. The seemingly contradictory coexistence of a high sheet resistance and high frequency quantum oscillations in the charge neutrality regime cannot be understood within the single-particle picture. We propose an interpretation that attributes our experimental observation to the Coulomb drag between the electron and hole gases, thus providing strong evidence of the significance of Coulomb interaction in this topological insulator.
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Affiliation(s)
- Di Xiao
- Department of Physics, the Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Chao-Xing Liu
- Department of Physics, the Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Nitin Samarth
- Department of Physics, the Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Lun-Hui Hu
- Department of Physics, Zhejiang University, Hangzhou, Zhejiang 310027, China
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5
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Electronic thermal conductivity in 2D topological insulator in a HgTe quantum well. Sci Rep 2019; 9:831. [PMID: 30696853 PMCID: PMC6351662 DOI: 10.1038/s41598-018-36705-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 10/28/2018] [Indexed: 11/09/2022] Open
Abstract
We have measured the differential resistance in a two-dimensional topological insulator (2DTI) in a HgTe quantum well, as a function of the applied dc current. The transport near the charge neutrality point is characterized by a pair of counter propagating gapless edge modes. In the presence of an electric field, the energy is transported by counter propagating channels in the opposite direction. We test a hot carrier effect model and demonstrate that the energy transfer complies with the Wiedemann Franz law near the charge neutrality point in the edge transport regime.
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6
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Krishtopenko SS, Teppe F. Quantum spin Hall insulator with a large bandgap, Dirac fermions, and bilayer graphene analog. SCIENCE ADVANCES 2018; 4:eaap7529. [PMID: 29725617 PMCID: PMC5930414 DOI: 10.1126/sciadv.aap7529] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 03/08/2018] [Indexed: 06/08/2023]
Abstract
The search for room temperature quantum spin Hall insulators (QSHIs) based on widely available materials and a controlled manufacturing process is one of the major challenges of today's topological physics. We propose a new class of semiconductor systems based on multilayer broken-gap quantum wells, in which the QSHI gap reaches 60 meV and remains insensitive to temperature. Depending on their layer thicknesses and geometry, these novel structures also host a graphene-like phase and a bilayer graphene analog. Our theoretical results significantly extend the application potential of topological materials based on III-V semiconductors.
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Affiliation(s)
- Sergey S. Krishtopenko
- Laboratoire Charles Coulomb (L2C), UMR CNRS 5221, University of Montpellier, 34095 Montpellier, France
- Institute for Physics of Microstructures, Russian Academy of Sciences, GSP-105, 603950 Nizhny Novgorod, Russia
| | - Frédéric Teppe
- Laboratoire Charles Coulomb (L2C), UMR CNRS 5221, University of Montpellier, 34095 Montpellier, France
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7
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de Vries FK, Timmerman T, Ostroukh VP, van Veen J, Beukman AJA, Qu F, Wimmer M, Nguyen BM, Kiselev AA, Yi W, Sokolich M, Manfra MJ, Marcus CM, Kouwenhoven LP. h/e Superconducting Quantum Interference through Trivial Edge States in InAs. PHYSICAL REVIEW LETTERS 2018; 120:047702. [PMID: 29437430 DOI: 10.1103/physrevlett.120.047702] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Indexed: 06/08/2023]
Abstract
Josephson junctions defined in strong spin orbit semiconductors are highly interesting for the search for topological systems. However, next to topological edge states that emerge in a sufficient magnetic field, trivial edge states can also occur. We study the trivial edge states with superconducting quantum interference measurements on nontopological InAs Josephson junctions. We observe a SQUID pattern, an indication of superconducting edge transport. Also, a remarkable h/e SQUID signal is observed that, as we find, stems from crossed Andreev states.
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Affiliation(s)
- Folkert K de Vries
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - Tom Timmerman
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - Viacheslav P Ostroukh
- Instituut-Lorentz, Universiteit Leiden, P.O. Box 9506, 2300 RA Leiden, The Netherlands
| | - Jasper van Veen
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - Arjan J A Beukman
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - Fanming Qu
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - Michael Wimmer
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - Binh-Minh Nguyen
- HRL Laboratories, 3011 Malibu Canyon Road, Malibu, California 90265, USA
| | - Andrey A Kiselev
- HRL Laboratories, 3011 Malibu Canyon Road, Malibu, California 90265, USA
| | - Wei Yi
- HRL Laboratories, 3011 Malibu Canyon Road, Malibu, California 90265, USA
| | - Marko Sokolich
- HRL Laboratories, 3011 Malibu Canyon Road, Malibu, California 90265, USA
| | - Michael J Manfra
- Department of Physics and Astronomy and Station Q Purdue, Purdue University, West Lafayette, Indiana 47907, USA
| | - Charles M Marcus
- Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Leo P Kouwenhoven
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA Delft, The Netherlands
- Microsoft Station Q Delft, 2600 GA Delft, The Netherlands
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8
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Du L, Li T, Lou W, Wu X, Liu X, Han Z, Zhang C, Sullivan G, Ikhlassi A, Chang K, Du RR. Tuning Edge States in Strained-Layer InAs/GaInSb Quantum Spin Hall Insulators. PHYSICAL REVIEW LETTERS 2017; 119:056803. [PMID: 28949710 DOI: 10.1103/physrevlett.119.056803] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Indexed: 06/07/2023]
Abstract
We report on a class of quantum spin Hall insulators (QSHIs) in strained-layer InAs/GaInSb quantum wells, in which the bulk gaps are enhanced up to fivefold as compared to the binary InAs/GaSb QSHI. Remarkably, with consequently increasing edge velocity, the edge conductance at zero and applied magnetic fields manifests time reversal symmetry-protected properties consistent with the Z_{2} topological insulator. The InAs/GaInSb bilayers offer a much sought-after platform for future studies and applications of the QSHI.
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Affiliation(s)
- Lingjie Du
- Department of Physics and Astronomy, Rice University, Houston, Texas 77251-1892, USA
| | - Tingxin Li
- Department of Physics and Astronomy, Rice University, Houston, Texas 77251-1892, USA
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
| | - Wenkai Lou
- SKLSM, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
| | - Xingjun Wu
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
| | - Xiaoxue Liu
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
| | - Zhongdong Han
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
| | - Chi Zhang
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
| | - Gerard Sullivan
- Teledyne Scientific and Imaging, Thousand Oaks, California 91603, USA
| | - Amal Ikhlassi
- Teledyne Scientific and Imaging, Thousand Oaks, California 91603, USA
| | - Kai Chang
- SKLSM, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
| | - Rui-Rui Du
- Department of Physics and Astronomy, Rice University, Houston, Texas 77251-1892, USA
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
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9
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Mani A, Benjamin C. Probing helicity and the topological origins of helicity via non-local Hanbury-Brown and Twiss correlations. Sci Rep 2017; 7:6954. [PMID: 28761065 PMCID: PMC5537406 DOI: 10.1038/s41598-017-06820-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 06/19/2017] [Indexed: 11/16/2022] Open
Abstract
Quantum Hall edge modes are chiral while quantum spin Hall edge modes are helical. However, unlike chiral edge modes which always occur in topological systems, quasi-helical edge modes may arise in a trivial insulator too. These trivial quasi-helical edge modes are not topologically protected and therefore need to be distinguished from helical edge modes arising due to topological reasons. Earlier conductance measurements were used to identify these helical states, in this work we report on the advantage of using the non local shot noise as a probe for the helical nature of these states as also their topological or otherwise origin and compare them with chiral quantum Hall states. We see that in similar set-ups affected by same degree of disorder and inelastic scattering, non local shot noise “HBT” correlations can be positive for helical edge modes but are always negative for the chiral quantum Hall edge modes. Further, while trivial quasi-helical edge modes exhibit negative non-local”HBT” charge correlations, topological helical edge modes can show positive non-local “HBT” charge correlation. We also study the non-local spin correlations and Fano factor for clues as regards both the distinction between chirality/helicity as well as the topological/trivial dichotomy for helical edge modes.
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Affiliation(s)
- Arjun Mani
- School of Physical Sciences, National Institute of Science Education & Research, HBNI, Jatni, 752050, India
| | - Colin Benjamin
- School of Physical Sciences, National Institute of Science Education & Research, HBNI, Jatni, 752050, India.
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10
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Karalic M, Mittag C, Tschirky T, Wegscheider W, Ensslin K, Ihn T. Lateral p-n Junction in an Inverted InAs/GaSb Double Quantum Well. PHYSICAL REVIEW LETTERS 2017; 118:206801. [PMID: 28581788 DOI: 10.1103/physrevlett.118.206801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Indexed: 06/07/2023]
Abstract
We present transport measurements on a lateral p-n junction in an inverted InAs/GaSb double quantum well at zero and nonzero perpendicular magnetic fields. At a zero magnetic field, the junction exhibits diodelike behavior in accordance with the presence of a hybridization gap. With an increasing magnetic field, we explore the quantum Hall regime where spin-polarized edge states with the same chirality are either reflected or transmitted at the junction, whereas those of opposite chirality undergo a mixing process, leading to full equilibration along the width of the junction independent of spin. These results lay the foundations for using p-n junctions in InAs/GaSb double quantum wells to probe the transition between the topological quantum spin Hall and quantum Hall states.
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Affiliation(s)
- Matija Karalic
- Solid State Physics Laboratory, ETH Zurich, 8093 Zurich, Switzerland
| | | | - Thomas Tschirky
- Solid State Physics Laboratory, ETH Zurich, 8093 Zurich, Switzerland
| | | | - Klaus Ensslin
- Solid State Physics Laboratory, ETH Zurich, 8093 Zurich, Switzerland
| | - Thomas Ihn
- Solid State Physics Laboratory, ETH Zurich, 8093 Zurich, Switzerland
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11
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Knolle J, Cooper NR. Anomalous de Haas-van Alphen Effect in InAs/GaSb Quantum Wells. PHYSICAL REVIEW LETTERS 2017; 118:176801. [PMID: 28498702 DOI: 10.1103/physrevlett.118.176801] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Indexed: 06/07/2023]
Abstract
The de Haas-van Alphen effect describes the periodic oscillation of the magnetization in a material as a function of an inverse applied magnetic field. It forms the basis of a well established procedure for measuring Fermi surface properties, and its observation is typically taken as a direct signature of a system being metallic. However, certain insulators can show similar oscillations of the magnetization from quantization of the energies of electron states in filled bands. Recently, the theory of such an anomalous dHvAE (AdHvAE) was worked out, but there has not yet been a clear experimental observation. Here, we show that the inverted narrow gap regime of InAs/GaSb quantum wells is an ideal platform for the observation of the AdHvAE. From our microscopic calculations, we make quantitative predictions for the relevant magnetic field and temperature regimes, and we describe unambiguous experimental signatures.
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Affiliation(s)
- Johannes Knolle
- T.C.M. Group, Cavendish Laboratory, J.J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Nigel R Cooper
- T.C.M. Group, Cavendish Laboratory, J.J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
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12
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Nichele F, Kjaergaard M, Suominen HJ, Skolasinski R, Wimmer M, Nguyen BM, Kiselev AA, Yi W, Sokolich M, Manfra MJ, Qu F, Beukman AJA, Kouwenhoven LP, Marcus CM. Giant Spin-Orbit Splitting in Inverted InAs/GaSb Double Quantum Wells. PHYSICAL REVIEW LETTERS 2017; 118:016801. [PMID: 28106408 DOI: 10.1103/physrevlett.118.016801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Indexed: 06/06/2023]
Abstract
Transport measurements in inverted InAs/GaSb quantum wells reveal a giant spin-orbit splitting of the energy bands close to the hybridization gap. The splitting results from the interplay of electron-hole mixing and spin-orbit coupling, and can exceed the hybridization gap. We experimentally investigate the band splitting as a function of top gate voltage for both electronlike and holelike states. Unlike conventional, noninverted two-dimensional electron gases, the Fermi energy in InAs/GaSb can cross a single spin-resolved band, resulting in full spin-orbit polarization. In the fully polarized regime we observe exotic transport phenomena such as quantum Hall plateaus evolving in e^{2}/h steps and a nontrivial Berry phase.
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Affiliation(s)
- Fabrizio Nichele
- Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Morten Kjaergaard
- Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Henri J Suominen
- Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Rafal Skolasinski
- QuTech, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - Michael Wimmer
- QuTech, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - Binh-Minh Nguyen
- HRL Laboratories, 3011 Malibu Canyon Road, Malibu, California 90265, USA
| | - Andrey A Kiselev
- HRL Laboratories, 3011 Malibu Canyon Road, Malibu, California 90265, USA
| | - Wei Yi
- HRL Laboratories, 3011 Malibu Canyon Road, Malibu, California 90265, USA
| | - Marko Sokolich
- HRL Laboratories, 3011 Malibu Canyon Road, Malibu, California 90265, USA
| | - Michael J Manfra
- Department of Physics and Astronomy and Station Q Purdue, Purdue University, West Lafayette, Indiana 47907, USA, School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907, USA, School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907, USA. and Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
| | - Fanming Qu
- QuTech, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - Arjan J A Beukman
- QuTech, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - Leo P Kouwenhoven
- QuTech, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - Charles M Marcus
- Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
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13
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Rocci M, Rossella F, Gomes UP, Zannier V, Rossi F, Ercolani D, Sorba L, Beltram F, Roddaro S. Tunable Esaki Effect in Catalyst-Free InAs/GaSb Core-Shell Nanowires. NANO LETTERS 2016; 16:7950-7955. [PMID: 27960509 DOI: 10.1021/acs.nanolett.6b04260] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We demonstrate tunable bistability and a strong negative differential resistance in InAs/GaSb core-shell nanowire devices embedding a radial broken-gap heterojunction. Nanostructures have been grown using a catalyst-free synthesis on a Si substrate. Current-voltage characteristics display a top peak-to-valley ratio of 4.8 at 4.2 K and 2.2 at room temperature. The Esaki effect can be modulated-or even completely quenched-by field effect, by controlling the band bending profile along the azimuthal angle of the radial heterostructure. Hysteretic behavior is also observed in the presence of a suitable resistive load. Our results indicate that high-quality broken-gap devices can be obtained using Au-free growth.
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Affiliation(s)
- M Rocci
- NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR , Piazza S. Silvestro 12, I-56127 Pisa, Italy
| | - F Rossella
- NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR , Piazza S. Silvestro 12, I-56127 Pisa, Italy
| | - U P Gomes
- NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR , Piazza S. Silvestro 12, I-56127 Pisa, Italy
| | - V Zannier
- NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR , Piazza S. Silvestro 12, I-56127 Pisa, Italy
| | - F Rossi
- IMEM-CNR ,Parco Area delle Scienze 37/A, I-43010 Parma, Italy
| | - D Ercolani
- NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR , Piazza S. Silvestro 12, I-56127 Pisa, Italy
| | - L Sorba
- NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR , Piazza S. Silvestro 12, I-56127 Pisa, Italy
| | - F Beltram
- NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR , Piazza S. Silvestro 12, I-56127 Pisa, Italy
| | - S Roddaro
- NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR , Piazza S. Silvestro 12, I-56127 Pisa, Italy
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14
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Nguyen BM, Kiselev AA, Noah R, Yi W, Qu F, Beukman AJA, de Vries FK, van Veen J, Nadj-Perge S, Kouwenhoven LP, Kjaergaard M, Suominen HJ, Nichele F, Marcus CM, Manfra MJ, Sokolich M. Decoupling Edge Versus Bulk Conductance in the Trivial Regime of an InAs/GaSb Double Quantum Well Using Corbino Ring Geometry. PHYSICAL REVIEW LETTERS 2016; 117:077701. [PMID: 27563999 DOI: 10.1103/physrevlett.117.077701] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Indexed: 06/06/2023]
Abstract
A Corbino ring geometry is utilized to analyze edge and bulk conductance of InAs/GaSb quantum well structures. We show that edge conductance exists in the trivial regime of this theoretically predicted topological system with a temperature-insensitive linear resistivity per unit length in the range of 2 kΩ/μm. A resistor network model of the device is developed to decouple the edge conductance from the bulk conductance, providing a quantitative technique to further investigate the nature of this trivial edge conductance, conclusively identified here as being of n type.
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Affiliation(s)
- Binh-Minh Nguyen
- HRL Laboratories, 3011 Malibu Canyon Road, Malibu, California 90265, USA
| | - Andrey A Kiselev
- HRL Laboratories, 3011 Malibu Canyon Road, Malibu, California 90265, USA
| | - Ramsey Noah
- HRL Laboratories, 3011 Malibu Canyon Road, Malibu, California 90265, USA
| | - Wei Yi
- HRL Laboratories, 3011 Malibu Canyon Road, Malibu, California 90265, USA
| | - Fanming Qu
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - Arjan J A Beukman
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - Folkert K de Vries
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - Jasper van Veen
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - Stevan Nadj-Perge
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - Leo P Kouwenhoven
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - Morten Kjaergaard
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Henri J Suominen
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Fabrizio Nichele
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Charles M Marcus
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Michael J Manfra
- Department of Physics and Astronomy, and Station Q Purdue, Purdue University, West Lafayette, Indiana 47907, USA
| | - Marko Sokolich
- HRL Laboratories, 3011 Malibu Canyon Road, Malibu, California 90265, USA
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15
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O'Farrell ECT, Tan JY, Yeo Y, Koon GKW, Özyilmaz B, Watanabe K, Taniguchi T. Rashba Interaction and Local Magnetic Moments in a Graphene-BN Heterostructure Intercalated with Au. PHYSICAL REVIEW LETTERS 2016; 117:076603. [PMID: 27563982 DOI: 10.1103/physrevlett.117.076603] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Indexed: 06/06/2023]
Abstract
We intercalate a van der Waals heterostructure of graphene and hexagonal boron nitride with Au, by encapsulation, and show that the Au at the interface is two dimensional. Charge transfer upon current annealing indicates the redistribution of the Au and induces splitting of the graphene band structure. The effect of an in-plane magnetic field confirms that the splitting is due to spin splitting and that the spin polarization is in the plane, characteristic of a Rashba interaction with a magnitude of approximately 25 meV. Consistent with the presence of an intrinsic interfacial electric field we show that the splitting can be enhanced by an applied displacement field in dual gated samples. A giant negative magnetoresistance, up to 75%, and a field induced anomalous Hall effect at magnetic fields <1 T are observed. These demonstrate that the hybridized Au has a magnetic moment and suggests the proximity to the formation of a collective magnetic phase. These effects persist close to room temperature.
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Affiliation(s)
- E C T O'Farrell
- Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore, Singapore 117546, Singapore and Department of Physics, National University of Singapore, Singapore 117542, Singapore
| | - J Y Tan
- Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore, Singapore 117546, Singapore and Department of Physics, National University of Singapore, Singapore 117542, Singapore
| | - Y Yeo
- Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore, Singapore 117546, Singapore and Department of Physics, National University of Singapore, Singapore 117542, Singapore
| | - G K W Koon
- Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore, Singapore 117546, Singapore and Department of Physics, National University of Singapore, Singapore 117542, Singapore
| | - B Özyilmaz
- Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore, Singapore 117546, Singapore and Department of Physics, National University of Singapore, Singapore 117542, Singapore
| | - K Watanabe
- National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - T Taniguchi
- National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
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16
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Gluschke JG, Leijnse M, Ganjipour B, Dick KA, Linke H, Thelander C. Characterization of Ambipolar GaSb/InAs Core-Shell Nanowires by Thermovoltage Measurements. ACS NANO 2015; 9:7033-7040. [PMID: 26090774 DOI: 10.1021/acsnano.5b01495] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In semiconductor heterostructures with a type II band alignment, such as GaSb-InAs, conduction can be tuned from electron- to hole-dominated using an electrostatic gate. However, traditional conductance measurements give no direct information on the carrier type, and thus limit the ability to distinguish transport effects originating from the two materials. Here, we employ thermovoltage measurements to GaSb/InAs core-shell nanowires, and reliably identify the dominant carrier type at room temperature as well as in the quantum transport regime at 4.2 K, even in cases where the conductance measurement does not allow for such a distinction. In addition, we show that theoretical modeling using the conductance data as input can reproduce the measured thermovoltage under the assumption that electron and hole states shift differently in energy with the applied gate voltage.
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Affiliation(s)
- Jan G Gluschke
- †Solid State Physics and Nanometer Structure Consortium (nmC@LU), Lund University, Box 118, S-22100 Lund, Sweden
- ‡School of Physics, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Martin Leijnse
- †Solid State Physics and Nanometer Structure Consortium (nmC@LU), Lund University, Box 118, S-22100 Lund, Sweden
| | - Bahram Ganjipour
- †Solid State Physics and Nanometer Structure Consortium (nmC@LU), Lund University, Box 118, S-22100 Lund, Sweden
| | - Kimberly A Dick
- †Solid State Physics and Nanometer Structure Consortium (nmC@LU), Lund University, Box 118, S-22100 Lund, Sweden
- §Center for Analysis and Synthesis, Lund University, Box 124, S-22100 Lund, Sweden
| | - Heiner Linke
- †Solid State Physics and Nanometer Structure Consortium (nmC@LU), Lund University, Box 118, S-22100 Lund, Sweden
| | - Claes Thelander
- †Solid State Physics and Nanometer Structure Consortium (nmC@LU), Lund University, Box 118, S-22100 Lund, Sweden
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