1
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Bakhshipour Z, Hosseini MV. Electron-electron interactions in partially mixed helical states. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2024; 36:395601. [PMID: 38906127 DOI: 10.1088/1361-648x/ad5ad2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2024] [Accepted: 06/21/2024] [Indexed: 06/23/2024]
Abstract
We theoretically study the effect of electron-electron interactions in one-dimensional partially mixed helical states. These helical states can be realized at the edges of two-dimensional topological insulators with partially broken time-reversal symmetry, resulting in helical gapped states. Using the bosonization method and renormalization group analysis, we identify weak gap, crossover, and strong gap regimes in the phase diagram. We find that strong electron-electron interaction mixes the helicity of the states, leading to the relevant strong gap regime. We investigate the charge and spin density wave correlation functions in different relevancy regimes of the gap mediated by interactions, where in the case of strong repulsive interaction, the spin density wave dominates the charge density wave. Additionally, employing the Memory function technique, we calculate the effect of mixed helicity on the charge transport in a sufficiently long edge. We find a non-uniform temperature dependence for the charge conductivity in both the strong and weak gap regimes with distinct features.
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Affiliation(s)
- Zeinab Bakhshipour
- Department of Physics, Faculty of Science, University of Zanjan, Zanjan 45371-38791, Iran
| | - Mir Vahid Hosseini
- Department of Physics, Faculty of Science, University of Zanjan, Zanjan 45371-38791, Iran
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2
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Chen L, Wu AX, Tulu N, Wang J, Juanson A, Watanabe K, Taniguchi T, Pettes MT, Campbell MA, Xu M, Gadre CA, Zhou Y, Chen H, Cao P, Jauregui LA, Wu R, Pan X, Sanchez-Yamagishi JD. Exceptional electronic transport and quantum oscillations in thin bismuth crystals grown inside van der Waals materials. NATURE MATERIALS 2024; 23:741-746. [PMID: 38740956 DOI: 10.1038/s41563-024-01894-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 04/09/2024] [Indexed: 05/16/2024]
Abstract
Confining materials to two-dimensional forms changes the behaviour of the electrons and enables the creation of new devices. However, most materials are challenging to produce as uniform, thin crystals. Here we present a synthesis approach where thin crystals are grown in a nanoscale mould defined by atomically flat van der Waals (vdW) materials. By heating and compressing bismuth in a vdW mould made of hexagonal boron nitride, we grow ultraflat bismuth crystals less than 10 nm thick. Due to quantum confinement, the bismuth bulk states are gapped, isolating intrinsic Rashba surface states for transport studies. The vdW-moulded bismuth shows exceptional electronic transport, enabling the observation of Shubnikov-de Haas quantum oscillations originating from the (111) surface state Landau levels. By measuring the gate-dependent magnetoresistance, we observe multi-carrier quantum oscillations and Landau level splitting, with features originating from both the top and bottom surfaces. Our vdW mould growth technique establishes a platform for electronic studies and control of bismuth's Rashba surface states and topological boundary modes1-3. Beyond bismuth, the vdW-moulding approach provides a low-cost way to synthesize ultrathin crystals and directly integrate them into a vdW heterostructure.
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Affiliation(s)
- Laisi Chen
- Department of Physics and Astronomy, University of California Irvine, Irvine, CA, USA
| | - Amy X Wu
- Department of Physics and Astronomy, University of California Irvine, Irvine, CA, USA
| | - Naol Tulu
- Department of Physics and Astronomy, University of California Irvine, Irvine, CA, USA
| | - Joshua Wang
- Department of Physics and Astronomy, University of California Irvine, Irvine, CA, USA
| | - Adrian Juanson
- Department of Physics and Astronomy, California State University Long Beach, Long Beach, CA, USA
| | - Kenji Watanabe
- Research Center for Electronic and Optical Materials, National Institute for Materials Science, Tsukuba, Japan
| | - Takashi Taniguchi
- Research Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba, Japan
| | - Michael T Pettes
- Center for Integrated Nanotechnologies (CINT), Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Marshall A Campbell
- Department of Physics and Astronomy, University of California Irvine, Irvine, CA, USA
- Center for Integrated Nanotechnologies (CINT), Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Mingjie Xu
- Irvine Materials Research Institute, University of California Irvine, Irvine, CA, USA
| | - Chaitanya A Gadre
- Department of Physics and Astronomy, University of California Irvine, Irvine, CA, USA
| | - Yinong Zhou
- Department of Physics and Astronomy, University of California Irvine, Irvine, CA, USA
| | - Hangman Chen
- Department of Mechanical and Aerospace Engineering, University of California Irvine, Irvine, CA, USA
| | - Penghui Cao
- Department of Mechanical and Aerospace Engineering, University of California Irvine, Irvine, CA, USA
| | - Luis A Jauregui
- Department of Physics and Astronomy, University of California Irvine, Irvine, CA, USA
| | - Ruqian Wu
- Department of Physics and Astronomy, University of California Irvine, Irvine, CA, USA
| | - Xiaoqing Pan
- Department of Physics and Astronomy, University of California Irvine, Irvine, CA, USA
- Irvine Materials Research Institute, University of California Irvine, Irvine, CA, USA
- Department of Materials Science and Engineering, University of California Irvine, Irvine, CA, USA
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3
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Huang S, Ghosh N, Niu C, Chen YP, Ye PD, Xu X. Optically Gated Electrostatic Field-Effect Thermal Transistor. NANO LETTERS 2024; 24:5139-5145. [PMID: 38639471 DOI: 10.1021/acs.nanolett.3c05085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/20/2024]
Abstract
Dynamic tuning of thermal transport in solids is scientifically intriguing with wide applications for thermal transport control in electronic devices. In this work, we demonstrate a thermal transistor, a device in which heat flow can be regulated using external control, realized in a topological insulator (TI) through the topological surface states. The tuning of thermal transport is achieved by using optical gating of a thin dielectric layer deposited on the TI film. The gate-dependent thermal conductivity is measured using micro-Raman thermometry. The transistor has a large ON/OFF ratio of 2.8 at room temperature and can be continuously and repetitively switched in tens of seconds by optical gating and potentially much faster by electrical gating. Such thermal transistors with a large ON/OFF ratio and fast switching times offer the possibilities of smart thermal devices for active thermal management and control in future electronic systems.
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Affiliation(s)
- Shouyuan Huang
- School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, United States
| | - Neil Ghosh
- School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, United States
| | - Chang Niu
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, United States
- Elmore Family School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Yong P Chen
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, United States
- Elmore Family School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907, United States
- Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907, United States
- Purdue Quantum Science and Engineering Institute, Purdue University, West Lafayette, Indiana 47907, United States
| | - Peide D Ye
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, United States
- Elmore Family School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907, United States
- Purdue Quantum Science and Engineering Institute, Purdue University, West Lafayette, Indiana 47907, United States
| | - Xianfan Xu
- School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, United States
- Elmore Family School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907, United States
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4
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Jin G, Kim SH, Han HJ. Synthesis and Future Electronic Applications of Topological Nanomaterials. Int J Mol Sci 2023; 25:400. [PMID: 38203574 PMCID: PMC10779379 DOI: 10.3390/ijms25010400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 12/19/2023] [Accepted: 12/22/2023] [Indexed: 01/12/2024] Open
Abstract
Over the last ten years, the discovery of topological materials has opened up new areas in condensed matter physics. These materials are noted for their distinctive electronic properties, unlike conventional insulators and metals. This discovery has not only spurred new research areas but also offered innovative approaches to electronic device design. A key aspect of these materials is now that transforming them into nanostructures enhances the presence of surface or edge states, which are the key components for their unique electronic properties. In this review, we focus on recent synthesis methods, including vapor-liquid-solid (VLS) growth, chemical vapor deposition (CVD), and chemical conversion techniques. Moreover, the scaling down of topological nanomaterials has revealed new electronic and magnetic properties due to quantum confinement. This review covers their synthesis methods and the outcomes of topological nanomaterials and applications, including quantum computing, spintronics, and interconnects. Finally, we address the materials and synthesis challenges that need to be resolved prior to the practical application of topological nanomaterials in advanced electronic devices.
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Affiliation(s)
- Gangtae Jin
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853, USA;
| | - Seo-Hyun Kim
- Department of Environment and Energy Engineering, Sungshin Women’s University, Seoul 01133, Republic of Korea;
| | - Hyeuk-Jin Han
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853, USA;
- Department of Environment and Energy Engineering, Sungshin Women’s University, Seoul 01133, Republic of Korea;
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5
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Impedance spectroscopy data for 2D biintercalate clathrate InSe<<NaNO2>+<FeCl3>>. APPLIED NANOSCIENCE 2023. [DOI: 10.1007/s13204-023-02804-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
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6
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Aiello CD, Abendroth JM, Abbas M, Afanasev A, Agarwal S, Banerjee AS, Beratan DN, Belling JN, Berche B, Botana A, Caram JR, Celardo GL, Cuniberti G, Garcia-Etxarri A, Dianat A, Diez-Perez I, Guo Y, Gutierrez R, Herrmann C, Hihath J, Kale S, Kurian P, Lai YC, Liu T, Lopez A, Medina E, Mujica V, Naaman R, Noormandipour M, Palma JL, Paltiel Y, Petuskey W, Ribeiro-Silva JC, Saenz JJ, Santos EJG, Solyanik-Gorgone M, Sorger VJ, Stemer DM, Ugalde JM, Valdes-Curiel A, Varela S, Waldeck DH, Wasielewski MR, Weiss PS, Zacharias H, Wang QH. A Chirality-Based Quantum Leap. ACS NANO 2022; 16:4989-5035. [PMID: 35318848 PMCID: PMC9278663 DOI: 10.1021/acsnano.1c01347] [Citation(s) in RCA: 58] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
There is increasing interest in the study of chiral degrees of freedom occurring in matter and in electromagnetic fields. Opportunities in quantum sciences will likely exploit two main areas that are the focus of this Review: (1) recent observations of the chiral-induced spin selectivity (CISS) effect in chiral molecules and engineered nanomaterials and (2) rapidly evolving nanophotonic strategies designed to amplify chiral light-matter interactions. On the one hand, the CISS effect underpins the observation that charge transport through nanoscopic chiral structures favors a particular electronic spin orientation, resulting in large room-temperature spin polarizations. Observations of the CISS effect suggest opportunities for spin control and for the design and fabrication of room-temperature quantum devices from the bottom up, with atomic-scale precision and molecular modularity. On the other hand, chiral-optical effects that depend on both spin- and orbital-angular momentum of photons could offer key advantages in all-optical and quantum information technologies. In particular, amplification of these chiral light-matter interactions using rationally designed plasmonic and dielectric nanomaterials provide approaches to manipulate light intensity, polarization, and phase in confined nanoscale geometries. Any technology that relies on optimal charge transport, or optical control and readout, including quantum devices for logic, sensing, and storage, may benefit from chiral quantum properties. These properties can be theoretically and experimentally investigated from a quantum information perspective, which has not yet been fully developed. There are uncharted implications for the quantum sciences once chiral couplings can be engineered to control the storage, transduction, and manipulation of quantum information. This forward-looking Review provides a survey of the experimental and theoretical fundamentals of chiral-influenced quantum effects and presents a vision for their possible future roles in enabling room-temperature quantum technologies.
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Affiliation(s)
- Clarice D. Aiello
- California
NanoSystems Institute, University of California,
Los Angeles, Los Angeles, California 90095, United States
- Department
of Electrical and Computer Engineering, University of California, Los Angeles, Los Angeles, California 90095, United States
| | - John M. Abendroth
- Laboratory
for Solid State Physics, ETH Zürich, Zürich 8093, Switzerland
| | - Muneer Abbas
- Department
of Microbiology, Howard University, Washington, D.C. 20059, United States
| | - Andrei Afanasev
- Department
of Physics, George Washington University, Washington, D.C. 20052, United States
| | - Shivang Agarwal
- Department
of Electrical and Computer Engineering, University of California, Los Angeles, Los Angeles, California 90095, United States
| | - Amartya S. Banerjee
- California
NanoSystems Institute, University of California,
Los Angeles, Los Angeles, California 90095, United States
- Department
of Materials Science and Engineering, University
of California, Los Angeles, Los Angeles, California 90095, United States
| | - David N. Beratan
- Departments
of Chemistry, Biochemistry, and Physics, Duke University, Durham, North Carolina 27708, United States
| | - Jason N. Belling
- California
NanoSystems Institute, University of California,
Los Angeles, Los Angeles, California 90095, United States
- Department
of Chemistry and Biochemistry, University
of California, Los Angeles, Los Angeles, California 90095, United States
| | - Bertrand Berche
- Laboratoire
de Physique et Chimie Théoriques, UMR Université de Lorraine-CNRS, 7019 54506 Vandœuvre les
Nancy, France
| | - Antia Botana
- Department
of Physics, Arizona State University, Tempe, Arizona 85287, United States
| | - Justin R. Caram
- Department
of Chemistry and Biochemistry, University
of California, Los Angeles, Los Angeles, California 90095, United States
| | - Giuseppe Luca Celardo
- Institute
of Physics, Benemerita Universidad Autonoma
de Puebla, Apartado Postal J-48, 72570, Mexico
- Department
of Physics and Astronomy, University of
Florence, 50019 Sesto Fiorentino, Italy
| | - Gianaurelio Cuniberti
- Institute
for Materials Science and Max Bergmann Center of Biomaterials, Dresden University of Technology, 01062 Dresden, Germany
| | - Aitzol Garcia-Etxarri
- Donostia
International Physics Center, Paseo Manuel de Lardizabal 4, 20018 Donostia, San Sebastian, Spain
- IKERBASQUE,
Basque Foundation for Science, Maria Diaz de Haro 3, 48013 Bilbao, Spain
| | - Arezoo Dianat
- Institute
for Materials Science and Max Bergmann Center of Biomaterials, Dresden University of Technology, 01062 Dresden, Germany
| | - Ismael Diez-Perez
- Department
of Chemistry, Faculty of Natural and Mathematical Sciences, King’s College London, 7 Trinity Street, London SE1 1DB, United Kingdom
| | - Yuqi Guo
- School
for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287, United States
| | - Rafael Gutierrez
- Institute
for Materials Science and Max Bergmann Center of Biomaterials, Dresden University of Technology, 01062 Dresden, Germany
| | - Carmen Herrmann
- Department
of Chemistry, University of Hamburg, 20146 Hamburg, Germany
| | - Joshua Hihath
- Department
of Electrical and Computer Engineering, University of California, Davis, Davis, California 95616, United States
| | - Suneet Kale
- School
of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, United States
| | - Philip Kurian
- Quantum
Biology Laboratory, Graduate School, Howard
University, Washington, D.C. 20059, United States
| | - Ying-Cheng Lai
- School
of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85287, United States
| | - Tianhan Liu
- California
NanoSystems Institute, University of California,
Los Angeles, Los Angeles, California 90095, United States
- Department
of Chemistry and Biochemistry, University
of California, Los Angeles, Los Angeles, California 90095, United States
| | - Alexander Lopez
- Escuela
Superior Politécnica del Litoral, ESPOL, Campus Gustavo Galindo Km. 30.5 Vía Perimetral, PO Box 09-01-5863, Guayaquil 090902, Ecuador
| | - Ernesto Medina
- Departamento
de Física, Colegio de Ciencias e Ingeniería, Universidad San Francisco de Quito, Av. Diego de Robles
y Vía Interoceánica, Quito 170901, Ecuador
| | - Vladimiro Mujica
- School
of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, United States
- Kimika
Fakultatea, Euskal Herriko Unibertsitatea, 20080 Donostia, Euskadi, Spain
| | - Ron Naaman
- Department
of Chemical and Biological Physics, Weizmann
Institute of Science, Rehovot 76100, Israel
| | - Mohammadreza Noormandipour
- Department
of Electrical and Computer Engineering, University of California, Los Angeles, Los Angeles, California 90095, United States
- TCM Group,
Cavendish Laboratory, University of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Julio L. Palma
- Department
of Chemistry, Pennsylvania State University, Lemont Furnace, Pennsylvania 15456, United States
| | - Yossi Paltiel
- Applied
Physics Department and the Center for Nano-Science and Nano-Technology, Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - William Petuskey
- School
of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, United States
| | - João Carlos Ribeiro-Silva
- Laboratory
of Genetics and Molecular Cardiology, Heart Institute, University of São Paulo Medical School, 05508-900 São
Paulo, Brazil
| | - Juan José Saenz
- Donostia
International Physics Center, Paseo Manuel de Lardizabal 4, 20018 Donostia, San Sebastian, Spain
- IKERBASQUE,
Basque Foundation for Science, Maria Diaz de Haro 3, 48013 Bilbao, Spain
| | - Elton J. G. Santos
- Institute
for Condensed Matter Physics and Complex Systems, School of Physics
and Astronomy, The University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
- Higgs Centre
for Theoretical Physics, The University
of Edinburgh, Edinburgh, EH9 3FD, United Kingdom
| | - Maria Solyanik-Gorgone
- Department
of Electrical and Computer Engineering, George Washington University, Washington, D.C. 20052, United States
| | - Volker J. Sorger
- Department
of Electrical and Computer Engineering, George Washington University, Washington, D.C. 20052, United States
| | - Dominik M. Stemer
- California
NanoSystems Institute, University of California,
Los Angeles, Los Angeles, California 90095, United States
- Department
of Materials Science and Engineering, University
of California, Los Angeles, Los Angeles, California 90095, United States
| | - Jesus M. Ugalde
- Kimika
Fakultatea, Euskal Herriko Unibertsitatea, 20080 Donostia, Euskadi, Spain
| | - Ana Valdes-Curiel
- California
NanoSystems Institute, University of California,
Los Angeles, Los Angeles, California 90095, United States
- Department
of Electrical and Computer Engineering, University of California, Los Angeles, Los Angeles, California 90095, United States
| | - Solmar Varela
- School
of Chemical Sciences and Engineering, Yachay
Tech University, 100119 Urcuquí, Ecuador
| | - David H. Waldeck
- Department
of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Michael R. Wasielewski
- Department
of Chemistry, Center for Molecular Quantum Transduction, and Institute
for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Paul S. Weiss
- California
NanoSystems Institute, University of California,
Los Angeles, Los Angeles, California 90095, United States
- Department
of Materials Science and Engineering, University
of California, Los Angeles, Los Angeles, California 90095, United States
- Department
of Chemistry and Biochemistry, University
of California, Los Angeles, Los Angeles, California 90095, United States
- Department
of Bioengineering, University of California,
Los Angeles, Los Angeles, California, 90095, United States
| | - Helmut Zacharias
- Center
for Soft Nanoscience, University of Münster, 48149 Münster, Germany
| | - Qing Hua Wang
- School
for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287, United States
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7
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Sondors R, Kunakova G, Jasulaneca L, Andzane J, Kauranens E, Bechelany M, Erts D. High-Yield Growth and Tunable Morphology of Bi 2Se 3 Nanoribbons Synthesized on Thermally Dewetted Au. NANOMATERIALS 2021; 11:nano11082020. [PMID: 34443851 PMCID: PMC8401543 DOI: 10.3390/nano11082020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 07/30/2021] [Accepted: 08/05/2021] [Indexed: 11/16/2022]
Abstract
The yield and morphology (length, width, thickness) of stoichiometric Bi2Se3 nanoribbons grown by physical vapor deposition is studied as a function of the diameters and areal number density of the Au catalyst nanoparticles of mean diameters 8–150 nm formed by dewetting Au layers of thicknesses 1.5–16 nm. The highest yield of the Bi2Se3 nanoribbons is reached when synthesized on dewetted 3 nm thick Au layer (mean diameter of Au nanoparticles ~10 nm) and exceeds the nanoribbon yield obtained in catalyst-free synthesis by almost 50 times. The mean lengths and thicknesses of the Bi2Se3 nanoribbons are directly proportional to the mean diameters of Au catalyst nanoparticles. In contrast, the mean widths of the Bi2Se3 nanoribbons do not show a direct correlation with the Au nanoparticle size as they depend on the contribution ratio of two main growth mechanisms—catalyst-free and vapor–liquid–solid deposition. The Bi2Se3 nanoribbon growth mechanisms in relation to the Au catalyst nanoparticle size and areal number density are discussed. Determined charge transport characteristics confirm the high quality of the synthesized Bi2Se3 nanoribbons, which, together with the high yield and tunable morphology, makes these suitable for application in a variety of nanoscale devices.
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Affiliation(s)
- Raitis Sondors
- Institute of Chemical Physics, University of Latvia, 19 Raina Blvd., LV-1586 Riga, Latvia; (R.S.); (G.K.); (L.J.); (J.A.); (E.K.)
| | - Gunta Kunakova
- Institute of Chemical Physics, University of Latvia, 19 Raina Blvd., LV-1586 Riga, Latvia; (R.S.); (G.K.); (L.J.); (J.A.); (E.K.)
| | - Liga Jasulaneca
- Institute of Chemical Physics, University of Latvia, 19 Raina Blvd., LV-1586 Riga, Latvia; (R.S.); (G.K.); (L.J.); (J.A.); (E.K.)
| | - Jana Andzane
- Institute of Chemical Physics, University of Latvia, 19 Raina Blvd., LV-1586 Riga, Latvia; (R.S.); (G.K.); (L.J.); (J.A.); (E.K.)
| | - Edijs Kauranens
- Institute of Chemical Physics, University of Latvia, 19 Raina Blvd., LV-1586 Riga, Latvia; (R.S.); (G.K.); (L.J.); (J.A.); (E.K.)
| | - Mikhael Bechelany
- Institut Européen des Membranes, IEM-UMR 5635, ENSCM, CNRS, University of Montpellier, Place Eugène Bataillon, 34095 Montpellier, France;
| | - Donats Erts
- Institute of Chemical Physics, University of Latvia, 19 Raina Blvd., LV-1586 Riga, Latvia; (R.S.); (G.K.); (L.J.); (J.A.); (E.K.)
- Faculty of Chemistry, University of Latvia, 19 Raina Blvd., LV-1586 Riga, Latvia
- Correspondence:
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8
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Xu H, Wang H, Zhou J, Li J. Pure spin photocurrent in non-centrosymmetric crystals: bulk spin photovoltaic effect. Nat Commun 2021; 12:4330. [PMID: 34267195 PMCID: PMC8282873 DOI: 10.1038/s41467-021-24541-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 06/16/2021] [Indexed: 02/06/2023] Open
Abstract
Spin current generators are critical components for spintronics-based information processing. In this work, we theoretically and computationally investigate the bulk spin photovoltaic (BSPV) effect for creating DC spin current under light illumination. The only requirement for BSPV is inversion symmetry breaking, thus it applies to a broad range of materials and can be readily integrated with existing semiconductor technologies. The BSPV effect is a cousin of the bulk photovoltaic (BPV) effect, whereby a DC charge current is generated under light. Thanks to the different selection rules on spin and charge currents, a pure spin current can be realized if the system possesses mirror symmetry or inversion-mirror symmetry. The mechanism of BSPV and the role of the electronic relaxation time [Formula: see text] are also elucidated. We apply our theory to several distinct materials, including monolayer transition metal dichalcogenides, anti-ferromagnetic bilayer MnBi2Te4, and the surface of topological crystalline insulator cubic SnTe.
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Affiliation(s)
- Haowei Xu
- Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Hua Wang
- Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Jian Zhou
- Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Ju Li
- Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
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9
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Zhao S, Li X, Dong B, Wang H, Wang H, Zhang Y, Han Z, Zhang H. Valley manipulation in monolayer transition metal dichalcogenides and their hybrid systems: status and challenges. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2021; 84:026401. [PMID: 33440363 DOI: 10.1088/1361-6633/abdb98] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Recently, the emerging conceptual valley-related devices have attracted much attention due to the progress on generating, controlling, and detecting the valley degree of freedom in the transition metal dichalcogenide (TMD) monolayers. In general, it is known that achieving valley degree of freedom with long valley lifetime is crucial in the implementation of valleytronic devices. Here, we provide a brief introduction of the basic understandings of valley degree of freedom. We as well review the recent experimental advancement in the modulation of valley degree of freedom. The strategies include optical/magnetic/electric field tuning, moiré patterns, plasmonic metasurface, defects and strain engineering. In addition, we summarize the corresponding mechanisms, which can help to obtain large degree of polarization and long valley lifetimes in monolayer TMDs. Based on these methods, two-dimensional valley-optoelectronic systems based on TMD heterostructures can be constructed, providing opportunities for such as the new paradigm in data processing and transmission. Challenges and perspectives on the development of valleytronics are highlighted as well.
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Affiliation(s)
- Siwen Zhao
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, People's Republic of China
- College of Materials Science and Engineering, Shenzhen University, Shenzhen 518060, People's Republic of China
| | - Xiaoxi Li
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, People's Republic of China
- School of Material Science and Engineering, University of Science and Technology of China, Hefei 230026, People's Republic of China
| | - Baojuan Dong
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Opto-Electronics, Shanxi University, Taiyuan 030006, People's Republic of China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, People's Republic of China
| | - Huide Wang
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, People's Republic of China
| | - Hanwen Wang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, People's Republic of China
- School of Material Science and Engineering, University of Science and Technology of China, Hefei 230026, People's Republic of China
| | - Yupeng Zhang
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, People's Republic of China
| | - Zheng Han
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Opto-Electronics, Shanxi University, Taiyuan 030006, People's Republic of China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, People's Republic of China
| | - Han Zhang
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, People's Republic of China
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10
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Chen JR, Tse PL, Krivorotov IN, Lu JG. Spin-momentum locking induced non-local voltage in topological insulator nanowire. NANOSCALE 2020; 12:22958-22962. [PMID: 33206099 DOI: 10.1039/d0nr06590k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The momentum and spin of charge carriers in the topological insulators are constrained to be perpendicular to each other due to the strong spin-orbit coupling. We have investigated this unique spin-momentum locking property in Sb2Te3 topological insulator nanowires by injecting spin-polarized electrons through magnetic tunnel junction electrodes. Non-local voltage measurements exhibit an asymmetry with respect to the magnetic field applied perpendicular to the nanowire channel, which is remarkably different from that of a non-local measurement in a channel that lacks spin-momentum locking. In stark contrast to conventional non-local spin valves, simultaneous reversal of magnetic moments of all magnetic contacts to the Sb2Te3 nanowire alters the non-local voltage. This unusual asymmetry is a clear signature of the spin-momentum locking in the Sb2Te3 nanowire surface states.
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Affiliation(s)
- Jen-Ru Chen
- Department of Physics and Astronomy, University of California, Irvine, California 92697, USA
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11
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Hosseini MV, Karimi Z, Davoodi J. Indirect exchange interaction between magnetic impurities in one-dimensional gapped helical states. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 33:085801. [PMID: 33212426 DOI: 10.1088/1361-648x/abcc11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We investigate theoretically indirect exchange interaction between magnetic impurities mediated by one-dimensional gapped helical states. Such states, containing massive Dirac fermions, may be realized on the edge of a two-dimensional topological insulator when time-reversal symmetry is weakly broken. We find that the indirect exchange interaction consists of Heisenberg, Dzyaloshinsky-Moriya, in-plane and out-of-plane Ising terms. These terms decay exponentially when the Fermi level lies inside the bandgap whereas the Dzyaloshinsky-Moriya term has smallest amplitude. Outside the bandgap, the massive helical states modify oscillatory behaviors of the range functions so that the period of oscillations decreases near the edge of band in terms of energy gap or Fermi energy. In addition, the out-of-plane Ising term vanishes in the case of zero-gap structure. Also, the oscillation amplitude of out-of-plane Ising term increases versus energy gap but it decreases as a function of Fermi energy. While the oscillation amplitudes of other components remain constant as functions of energy gap and Fermi energy. Analytical results are also obtained for subgap and over gap regimes. Furthermore, the effects of electron-electron interactions are analyzed.
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Affiliation(s)
- Mir Vahid Hosseini
- Department of Physics, Faculty of Science, University of Zanjan, Zanjan 45371-38791, Iran
| | - Zahra Karimi
- Department of Physics, Faculty of Science, University of Zanjan, Zanjan 45371-38791, Iran
| | - Jamal Davoodi
- Department of Physics, Faculty of Science, University of Zanjan, Zanjan 45371-38791, Iran
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12
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Premasiri K, Gao XPA. Tuning spin-orbit coupling in 2D materials for spintronics: a topical review. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:193001. [PMID: 30726777 DOI: 10.1088/1361-648x/ab04c7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Atomically-thin 2D materials have opened up new opportunities in the past decade in realizing novel electronic device concepts, owing to their unusual electronic properties. The recent progress made in the aspect of utilizing additional degrees of freedom of the electrons such as spin and valley suggests that 2D materials have a significant potential in replacing current electronic-charge-based semiconductor technology with spintronics and valleytronics. For spintronics, spin-orbit coupling plays a key role in manipulating the electrons' spin degree of freedom to encode and process information, and there are a host of recent studies exploring this facet of 2D materials. We review the recent advances in tuning spin-orbit coupling of 2D materials which are of notable importance to the progression of spintronics.
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Affiliation(s)
- Kasun Premasiri
- Department of Physics, Case Western Reserve University, 2076 Adelbert Road, Cleveland, OH 44106, United States of America
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13
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Silva JF, Vernek E. Modified exchange interaction between magnetic impurities in spin-orbit coupled quantum wires. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:135802. [PMID: 30665202 DOI: 10.1088/1361-648x/ab0076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Indirect exchange interaction between magnetic impurities in one dimensional systems is a matter of long discussions since Kittel has established that in the asymptotic limit it decays as the inverse of distance x between the impurities. In this work we investigate this problem in a quantum wire with Rashba spin-orbit coupling (SOC). By employing a second order perturbation theory we find that one additional oscillatory term appears in each of the Ruderman-Kittel-Kasuya-Yosida (RKKY), the Dzaloshinkii-Moryia and the Ising couplings. Remarkably, these extra terms resulting from the spin precession of the conduction electrons induced by the SOC do not decay as in the usual RKKY interaction. We show that these extra oscillations arise from the finite momenta band splitting induced by the spin-orbit coupling that modifies the spin-flip scatterings occurring at the Fermi energy. Our findings open up a new perspective in the long-distance magnetic interactions in solid state systems.
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Affiliation(s)
- Joelson F Silva
- Instituto de Física, Universidade Federal de Uberlândia, Uberlândia, Minas Gerais 38400-902, Brazil
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14
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Kunakova G, Galletti L, Charpentier S, Andzane J, Erts D, Léonard F, Spataru CD, Bauch T, Lombardi F. Bulk-free topological insulator Bi 2Se 3 nanoribbons with magnetotransport signatures of Dirac surface states. NANOSCALE 2018; 10:19595-19602. [PMID: 30325390 DOI: 10.1039/c8nr05500a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Many applications of topological insulators (TIs) as well as new phenomena require devices with reduced dimensions. While much progress has been made to realize thin films of TIs with low bulk carrier densities, nanostructures have not yet been reported with similar properties, despite the fact that reduced dimensions should help diminish the contributions from bulk carriers. Here we demonstrate that Bi2Se3 nanoribbons, grown by a simple catalyst-free physical-vapour deposition, have inherently low bulk carrier densities, and can be further made bulk-free by thickness reduction, thus revealing the high mobility topological surface states. Magnetotransport and Hall conductance measurements, in single nanoribbons, show that at thicknesses below 30 nm, the bulk transport is completely suppressed which is supported by self-consistent band-bending calculations. The results highlight the importance of material growth and geometrical confinement to properly exploit the unique properties of topological surface states.
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Affiliation(s)
- Gunta Kunakova
- Quantum Device Physics Laboratory, Department of Microtechnology and Nanoscience, Chalmers University of Technology, SE-41296 Gothenburg, Sweden.
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15
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Abstract
This review briefly describes the development of synthetic topological insulator materials in the application of advanced electronic devices. As a new class of quantum matter, topological insulators with insulating bulk and conducting surface states have attracted attention in more and more research fields other than condensed matter physics due to their intrinsic physical properties, which provides an excellent basis for novel nanoelectronic, optoelectronic, and spintronic device applications. In comparison to the mechanically exfoliated samples, the newly emerging topological insulator nanostructures prepared with various synthetical approaches are more intriguing because the conduction contribution of the surface states can be significantly enhanced due to the larger surface-to-volume ratio, better manifesting the unique properties of the gapless surface states. So far, these synthetic topological insulator nanostructures have been implemented in different electrically accessible device platforms via electrical, magnetic and optical characterizations for material investigations and device applications, which will be introduced in this review.
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16
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Hashimoto K, Tomimatsu T, Sato K, Hirayama Y. Scanning nuclear resonance imaging of a hyperfine-coupled quantum Hall system. Nat Commun 2018; 9:2215. [PMID: 29880822 PMCID: PMC5992213 DOI: 10.1038/s41467-018-04612-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 05/07/2018] [Indexed: 11/09/2022] Open
Abstract
Nuclear resonance (NR) is widely used to detect and characterise nuclear spin polarisation and conduction electron spin polarisation coupled by a hyperfine interaction. While the macroscopic aspects of such hyperfine-coupled systems have been addressed in most relevant studies, the essential role of local variation in both types of spin polarisation has been indicated in 2D semiconductor systems. In this study, we apply a recently developed local and highly sensitive NR based on a scanning probe to a hyperfine-coupled quantum Hall (QH) system in a 2D electron gas subject to a strong magnetic field. We succeed in imaging the NR intensity and Knight shift, uncovering the spatial distribution of both the nuclear and electron spin polarisation. The results reveal the microscopic origin of the nonequilibrium QH phenomena, and highlight the potential use of our technique in microscopic studies on various electron spin systems as well as their correlations with nuclear spins.
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Affiliation(s)
- Katsushi Hashimoto
- Graduate School of Sciences, Tohoku University, Sendai, 980-8578, Japan.
- Centre for Spintronics Research Network, Tohoku University, Sendai, 980-8578, Japan.
| | - Toru Tomimatsu
- Graduate School of Sciences, Tohoku University, Sendai, 980-8578, Japan
| | - Ken Sato
- Graduate School of Sciences, Tohoku University, Sendai, 980-8578, Japan
| | - Yoshiro Hirayama
- Graduate School of Sciences, Tohoku University, Sendai, 980-8578, Japan
- Centre for Spintronics Research Network, Tohoku University, Sendai, 980-8578, Japan
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17
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Zhang C, Lu HZ, Shen SQ, Chen YP, Xiu F. Towards the manipulation of topological states of matter: a perspective from electron transport. Sci Bull (Beijing) 2018; 63:580-594. [PMID: 36658845 DOI: 10.1016/j.scib.2018.04.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2018] [Revised: 04/02/2018] [Accepted: 04/04/2018] [Indexed: 01/21/2023]
Abstract
The introduction of topological invariants, ranging from insulators to metals, has provided new insights into the traditional classification of electronic states in condensed matter physics. A sudden change in the topological invariant at the boundary of a topological nontrivial system leads to the formation of exotic surface states that are dramatically different from its bulk. In recent years, significant advancements in the exploration of the physical properties of these topological systems and regarding device research related to spintronics and quantum computation have been made. Here, we review the progress of the characterization and manipulation of topological phases from the electron transport perspective and also the intriguing chiral/Majorana states that stem from them. We then discuss the future directions of research into these topological states and their potential applications.
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Affiliation(s)
- Cheng Zhang
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China; Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China
| | - Hai-Zhou Lu
- Institute for Quantum Science and Engineering and Department of Physics, South University of Science and Technology of China, Shenzhen 518055, China; Shenzhen Key Laboratory of Quantum Science and Engineering, Shenzhen 518055, China
| | - Shun-Qing Shen
- Department of Physics, The University of Hong Kong, Hong Kong, China
| | - Yong P Chen
- Department of Physics and Astronomy, Purdue University, West Lafayette 47907, USA; Birck Nanotechnology Center, Purdue University, West Lafayette 47907, USA; School of Electrical and Computer Engineering, Purdue University, West Lafayette 47907, USA
| | - Faxian Xiu
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China; Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China; Institute for Nanoelectronic Devices and Quantum Computing, Fudan University, Shanghai 200433, China.
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18
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Vaklinova K, Polyudov K, Burghard M, Kern K. Spin filter effect of hBN/Co detector electrodes in a 3D topological insulator spin valve. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2018; 30:105302. [PMID: 29393070 DOI: 10.1088/1361-648x/aaac90] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Topological insulators emerge as promising components of spintronic devices, in particular for applications where all-electrical spin control is essential. While the capability of these materials to generate spin-polarized currents is well established, only very little is known about the spin injection/extraction into/out of them. Here, we explore the switching behavior of lateral spin valves comprising the 3D topological insulator Bi2Te2Se as channel, which is separated from ferromagnetic Cobalt detector contacts by an ultrathin hexagonal boron nitride (hBN) tunnel barrier. The corresponding contact resistance displays a notable variation, which is correlated with a change of the switching characteristics of the spin valve. For contact resistances below ~5 kΩ, the hysteresis in the switching curve reverses upon reversing the applied current, as expected for spin-polarized currents carried by the helical surface states. By contrast, for higher contact resistances an opposite polarity of the hysteresis loop is observed, which is independent of the current direction, a behavior signifying negative spin detection efficiency of the multilayer hBN/Co contacts combined with bias-induced spin signal inversion. Our findings suggest the possibility to tune the spin exchange across the interface between a ferromagnetic metal and a topological insulator through the number of intervening hBN layers.
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Affiliation(s)
- Kristina Vaklinova
- Nanoscale Science Department, Max Planck Institute for Solid State Research, Heisenbergstr. 1, D-70569 Stuttgart, Germany
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19
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Chang SJ, Chuang PY, Chong CW, Chen YJ, Andrew Huang JC, Chen PW, Tseng YC. Heterostructured ferromagnet–topological insulator with dual-phase magnetic properties. RSC Adv 2018; 8:7785-7791. [PMID: 35539151 PMCID: PMC9078499 DOI: 10.1039/c8ra00068a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Accepted: 02/05/2018] [Indexed: 12/02/2022] Open
Abstract
The introduction of ferromagnetism at the surface of a topological insulator (TI) produces fascinating spin-charge phenomena. It has been assumed that these fascinating effects are associated with a homogeneous ferromagnetic (FM) layer possessing a single type of magnetic phase. However, we obtained phase separation within the FM layer of a Ni80Fe20/Bi2Se3 heterostructure. This phase separation was caused by the diffusion of Ni into Bi2Se3, forming a ternary magnetic phase of Ni:Bi2Se3. The inward diffusion of Ni led to the formation of an FeSe phase outward, transforming the original Ni80Fe20/Bi2Se3 into a sandwich structure comprising FeSe/Ni:Bi2Se3/Bi2Se3 with dual-phase magnetic characteristics similar to that driven by the proximity effect. Such a phenomenon might have been overlooked in previous studies with a strong focus on the proximity effect. X-ray magnetic spectroscopy revealed that FeSe and Ni:Bi2Se3 possess horizontal and perpendicular magnetic anisotropy, respectively. The overall magnetic order of the heterostructure can be easily tuned by adjusting the thickness of the Bi2Se3 as it compromises the magnetic orders of the two magnetic phases. This discovery is essential to the quantification of spin-charge phenomena in similar material combinations where the FM layer is composed of multiple elements. In this study we visualized thermodynamically stable chalcogen compounds in the vicinity of a Py/Bi2Se3 interface with dual magnetic order due to a phase separation effect.![]()
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Affiliation(s)
- Shu-Jui Chang
- Department of Materials Science & Engineering
- National Chiao Tung University
- Hsinchu
- Taiwan
| | - Pei-Yu Chuang
- Department of Physics
- National Cheng Kung University
- Tainan
- Taiwan
| | | | - Yu-Jung Chen
- Department of Materials Science & Engineering
- National Chiao Tung University
- Hsinchu
- Taiwan
| | - Jung-Chun Andrew Huang
- Department of Physics
- National Cheng Kung University
- Tainan
- Taiwan
- Advanced Optoelectronic Technology Center
| | - Po-Wen Chen
- Division of Physics
- Institute of Nuclear Energy Research
- Taoyuan
- Taiwan
| | - Yuan-Chieh Tseng
- Department of Materials Science & Engineering
- National Chiao Tung University
- Hsinchu
- Taiwan
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20
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Kung HH, Maiti S, Wang X, Cheong SW, Maslov DL, Blumberg G. Chiral Spin Mode on the Surface of a Topological Insulator. PHYSICAL REVIEW LETTERS 2017; 119:136802. [PMID: 29341673 DOI: 10.1103/physrevlett.119.136802] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2017] [Indexed: 05/05/2023]
Abstract
Using polarization-resolved resonant Raman spectroscopy, we explore collective spin excitations of the chiral surface states in a three dimensional topological insulator, Bi_{2}Se_{3}. We observe a sharp peak at 150 meV in the pseudovector A_{2} symmetry channel of the Raman spectra. By comparing the data with calculations, we identify this peak as the transverse collective spin mode of surface Dirac fermions. This mode, unlike a Dirac plasmon or a surface plasmon in the charge sector of excitations, is analogous to a spin wave in a partially polarized Fermi liquid, with spin-orbit coupling playing the role of an effective magnetic field.
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Affiliation(s)
- H-H Kung
- Department of Physics & Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - S Maiti
- Department of Physics, University of Florida, Gainesville, Florida 32611, USA
| | - X Wang
- Department of Physics & Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
- Rutgers Center for Emergent Materials, Rutgers University, Piscataway, New Jersey 08854, USA
| | - S-W Cheong
- Department of Physics & Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
- Rutgers Center for Emergent Materials, Rutgers University, Piscataway, New Jersey 08854, USA
| | - D L Maslov
- Department of Physics, University of Florida, Gainesville, Florida 32611, USA
- National High Magnetic Field Laboratory, Tallahassee, Florida 32310, USA
| | - G Blumberg
- Department of Physics & Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
- National Institute of Chemical Physics and Biophysics, 12618 Tallinn, Estonia
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21
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Tian W, Yu W, Shi J, Wang Y. The Property, Preparation and Application of Topological Insulators: A Review. MATERIALS (BASEL, SWITZERLAND) 2017; 10:E814. [PMID: 28773173 PMCID: PMC5551857 DOI: 10.3390/ma10070814] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 07/09/2017] [Accepted: 07/10/2017] [Indexed: 01/14/2023]
Abstract
Topological insulator (TI), a promising quantum and semiconductor material, has gapless surface state and narrow bulk band gap. Firstly, the properties, classifications and compounds of TI are introduced. Secondly, the preparation and doping of TI are assessed. Some results are listed. (1) Although various preparation methods are used to improve the crystal quality of the TI, it cannot reach the industrialization. Fermi level regulation still faces challenges; (2) The carrier type and lattice of TI are affected by non-magnetic impurities. The most promising property is the superconductivity at low temperature; (3) Magnetic impurities can destroy the time-reversal symmetry of the TI surface, which opens the band gap on the TI surface resulting in some novel physical effects such as quantum anomalous Hall effect (QAHE). Thirdly, this paper summarizes various applications of TI including photodetector, magnetic device, field-effect transistor (FET), laser, and so on. Furthermore, many of their parameters are compared based on TI and some common materials. It is found that TI-based devices exhibit excellent performance, but some parameters such as signal to noise ratio (S/N) are still lower than other materials. Finally, its advantages, challenges and future prospects are discussed. Overall, this paper provides an opportunity to improve crystal quality, doping regulation and application of TI.
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Affiliation(s)
- Wenchao Tian
- School of Electro-Mechanical Engineering, Xidian University, Number 2 Taibai South Road, Xi'an 710071, China.
| | - Wenbo Yu
- School of Electro-Mechanical Engineering, Xidian University, Number 2 Taibai South Road, Xi'an 710071, China.
| | - Jing Shi
- School of Electro-Mechanical Engineering, Xidian University, Number 2 Taibai South Road, Xi'an 710071, China.
| | - Yongkun Wang
- School of Electro-Mechanical Engineering, Xidian University, Number 2 Taibai South Road, Xi'an 710071, China.
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