1
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Yang X, Qiu L, Li Y, Xue HP, Liu JN, Sun R, Yang QL, Gai XS, Wei YS, Comstock AH, Sun D, Zhang XQ, He W, Hou Y, Cheng ZH. Anisotropic Nonlocal Damping in Ferromagnet/α-GeTe Bilayers Enabled by Splitting Energy Bands. PHYSICAL REVIEW LETTERS 2023; 131:186703. [PMID: 37977650 DOI: 10.1103/physrevlett.131.186703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 07/20/2023] [Accepted: 10/06/2023] [Indexed: 11/19/2023]
Abstract
The understanding and manipulation of anisotropic Gilbert damping is crucial for both fundamental research and versatile engineering and optimization. Although several works on anisotropic damping have been reported, no direct relationship between the band structure and anisotropic damping was established. Here, we observed an anisotropic damping in Fe/GeTe manipulated by the symmetric band structures of GeTe via angle-resolved photoemission spectroscopy. Moreover, the anisotropic damping can be modified by the symmetry of band structures. Our Letter provides insightful understandings of the anisotropic Gilbert damping in ferromagnets interfaced with Rashba semiconductors and suggests the possibility of manipulating the Gilbert damping by band engineering.
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Affiliation(s)
- Xu Yang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| | - Liang Qiu
- Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices, Center for Neutron Science and Technology, School of Physics, Sun Yat-Sen University, Guangzhou 510275, China
| | - Yan Li
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Hao-Pu Xue
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jia-Nan Liu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rui Sun
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qing-Lin Yang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xue-Song Gai
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yan-Sheng Wei
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Andrew H Comstock
- Department of Physics and Organic and Carbon Electronics Laboratory (ORCEL), North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Dali Sun
- Department of Physics and Organic and Carbon Electronics Laboratory (ORCEL), North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Xiang-Qun Zhang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Wei He
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Yusheng Hou
- Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices, Center for Neutron Science and Technology, School of Physics, Sun Yat-Sen University, Guangzhou 510275, China
| | - Zhao-Hua Cheng
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
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2
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Cullen JH, Atencia RB, Culcer D. Spin transfer torques due to the bulk states of topological insulators. NANOSCALE 2023; 15:8437-8446. [PMID: 37096561 DOI: 10.1039/d2nr05176a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Spin torques at topological insulator (TI)/ferromagnet interfaces have received considerable attention in recent years with a view towards achieving full electrical manipulation of magnetic degrees of freedom. The most important question in this field concerns the relative contributions of bulk and surface states to the spin torque, a matter that remains incompletely understood. Whereas the surface state contribution has been extensively studied, the contribution due to the bulk states has received comparatively little attention. Here we study spin torques due to TI bulk states and show that: (i) there is no spin-orbit torque due to the bulk states on a homogeneous magnetisation, in contrast to the surface states, which give rise to a spin-orbit torque via the well-known Edelstein effect. (ii) The bulk states give rise to a spin transfer torque (STT) due to the inhomogeneity of the magnetisation in the vicinity of the interface. This spin transfer torque, which has not been considered in TIs in the past, is somewhat unconventional since it arises from the interplay of the bulk TI spin-orbit coupling and the gradient of the monotonically decaying magnetisation inside the TI. Whereas we consider an idealised model in which the magnetisation gradient is small and the spin transfer torque is correspondingly small, we argue that in real samples the spin transfer torque should be sizable and may provide the dominant contribution due to the bulk states. We show that an experimental smoking gun for identifying the bulk states is the fact that the field-like component of the spin transfer torque generates a spin density with the same size but opposite sign for in-plane and out-of-plane magnetisations. This distinguishes them from the surface states, which are expected to give a spin density of a similar size and the same sign for both an in-plane and out-of-plane magnetisations.
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Affiliation(s)
- James H Cullen
- School of Physics, The University of New South Wales, Sydney 2052, Australia.
| | - Rhonald Burgos Atencia
- School of Physics, The University of New South Wales, Sydney 2052, Australia.
- Facultad de Ingenierías, Departamento de Ciencias Básicas, Universidad del Sinú, Cra.1w No. 38-153, 4536534, Montería, Córdoba 230002, Colombia
| | - Dimitrie Culcer
- School of Physics, The University of New South Wales, Sydney 2052, Australia.
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3
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Burn DM, Lin JC, Fujita R, Achinuq B, Bibby J, Singh A, Frisk A, van der Laan G, Hesjedal T. Spin pumping through nanocrystalline topological insulators. NANOTECHNOLOGY 2023; 34:275001. [PMID: 36947871 DOI: 10.1088/1361-6528/acc663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 03/21/2023] [Indexed: 06/18/2023]
Abstract
The topological surface states (TSSs) in topological insulators (TIs) offer exciting prospects for dissipationless spin transport. Common spin-based devices, such as spin valves, rely on trilayer structures in which a non-magnetic layer is sandwiched between two ferromagnetic (FM) layers. The major disadvantage of using high-quality single-crystalline TI films in this context is that a single pair of spin-momentum locked channels spans across the entire film, meaning that only a very small spin current can be pumped from one FM to the other, along the side walls of the film. On the other hand, using nanocrystalline TI films, in which the grains are large enough to avoid hybridization of the TSSs, will effectively increase the number of spin channels available for spin pumping. Here, we used an element-selective, x-ray based ferromagnetic resonance technique to demonstrate spin pumping from a FM layer at resonance through the TI layer and into the FM spin sink.
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Affiliation(s)
- David M Burn
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - Jheng-Cyuan Lin
- Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford, OX1 3PU, United Kingdom
| | - Ryuji Fujita
- Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford, OX1 3PU, United Kingdom
| | - Barat Achinuq
- Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford, OX1 3PU, United Kingdom
| | - Joshua Bibby
- Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford, OX1 3PU, United Kingdom
| | - Angadjit Singh
- Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford, OX1 3PU, United Kingdom
| | - Andreas Frisk
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - Gerrit van der Laan
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - Thorsten Hesjedal
- Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford, OX1 3PU, United Kingdom
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4
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Liu J, Hesjedal T. Magnetic Topological Insulator Heterostructures: A Review. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021:e2102427. [PMID: 34665482 DOI: 10.1002/adma.202102427] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 06/05/2021] [Indexed: 06/13/2023]
Abstract
Topological insulators (TIs) provide intriguing prospects for the future of spintronics due to their large spin-orbit coupling and dissipationless, counter-propagating conduction channels in the surface state. The combination of topological properties and magnetic order can lead to new quantum states including the quantum anomalous Hall effect that was first experimentally realized in Cr-doped (Bi,Sb)2 Te3 films. Since magnetic doping can introduce detrimental effects, requiring very low operational temperatures, alternative approaches are explored. Proximity coupling to magnetically ordered systems is an obvious option, with the prospect to raise the temperature for observing the various quantum effects. Here, an overview of proximity coupling and interfacial effects in TI heterostructures is presented, which provides a versatile materials platform for tuning the magnetic and topological properties of these exciting materials. An introduction is first given to the heterostructure growth by molecular beam epitaxy and suitable structural, electronic, and magnetic characterization techniques. Going beyond transition-metal-doped and undoped TI heterostructures, examples of heterostructures are discussed, including rare-earth-doped TIs, magnetic insulators, and antiferromagnets, which lead to exotic phenomena such as skyrmions and exchange bias. Finally, an outlook on novel heterostructures such as intrinsic magnetic TIs and systems including 2D materials is given.
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Affiliation(s)
- Jieyi Liu
- Clarendon Laboratory, Department of Physics University of Oxford, Parks Road, Oxford, OX1 3PU, UK
| | - Thorsten Hesjedal
- Clarendon Laboratory, Department of Physics University of Oxford, Parks Road, Oxford, OX1 3PU, UK
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5
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Bhattacharyya S, Akhgar G, Gebert M, Karel J, Edmonds MT, Fuhrer MS. Recent Progress in Proximity Coupling of Magnetism to Topological Insulators. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2007795. [PMID: 34185344 DOI: 10.1002/adma.202007795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 01/11/2021] [Indexed: 05/08/2023]
Abstract
Inducing long-range magnetic order in 3D topological insulators can gap the Dirac-like metallic surface states, leading to exotic new phases such as the quantum anomalous Hall effect or the axion insulator state. These magnetic topological phases can host robust, dissipationless charge and spin currents or unique magnetoelectric behavior, which can be exploited in low-energy electronics and spintronics applications. Although several different strategies have been successfully implemented to realize these states, to date these phenomena have been confined to temperatures below a few Kelvin. This review focuses on one strategy: inducing magnetic order in topological insulators by proximity of magnetic materials, which has the capability for room temperature operation, unlocking the potential of magnetic topological phases for applications. The unique advantages of this strategy, the important physical mechanisms facilitating magnetic proximity effect, and the recent progress to achieve, understand, and harness proximity-coupled magnetic order in topological insulators are discussed. Some emerging new phenomena and applications enabled by proximity coupling of magnetism and topological materials, such as skyrmions and the topological Hall effect, are also highlighted, and the authors conclude with an outlook on remaining challenges and opportunities in the field.
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Affiliation(s)
- Semonti Bhattacharyya
- School of Physics and Astronomy, Monash University, Victoria, 3800, Australia
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Victoria, 3800, Australia
| | - Golrokh Akhgar
- School of Physics and Astronomy, Monash University, Victoria, 3800, Australia
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Victoria, 3800, Australia
| | - Matthew Gebert
- School of Physics and Astronomy, Monash University, Victoria, 3800, Australia
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Victoria, 3800, Australia
| | - Julie Karel
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Victoria, 3800, Australia
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria, 3800, Australia
| | - Mark T Edmonds
- School of Physics and Astronomy, Monash University, Victoria, 3800, Australia
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Victoria, 3800, Australia
| | - Michael S Fuhrer
- School of Physics and Astronomy, Monash University, Victoria, 3800, Australia
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Victoria, 3800, Australia
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6
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Cheng Y, Lee AJ, Wu G, Pelekhov DV, Hammel PC, Yang F. Nonlocal Uniform-Mode Ferromagnetic Resonance Spin Pumping. NANO LETTERS 2020; 20:7257-7262. [PMID: 32955896 DOI: 10.1021/acs.nanolett.0c02640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Nonlocal spin transport using lateral structures is attractive for spintronic devices. Typically, a spin current is generated by a ferromagnetic (FM) or a heavy metal (HM) electrode in a nonlocal structure, which can be detected by another FM or HM electrode. Here, we report a new nonlocal spin injection scheme using uniform-mode ferromagnetic resonance (FMR) spin pumping in Pt/Y3Fe5O12 (YIG) lateral structures. This scheme is enabled by well-separated resonant fields of Pt/YIG and bare YIG due to substantial change of anisotropy in YIG films induced by a Pt overlayer, allowing for clearly distinguishable local and nonlocal spin pumping. Our results show that the spin decay length of nonlocal uniform-mode spin pumping in 20 nm YIG films is 2.1 μm at room temperature.
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Affiliation(s)
- Yang Cheng
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, United States
| | - Aidan J Lee
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, United States
| | - Guanzhong Wu
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, United States
| | - Denis V Pelekhov
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, United States
| | - P Chris Hammel
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, United States
| | - Fengyuan Yang
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, United States
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7
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Liu T, Kally J, Pillsbury T, Liu C, Chang H, Ding J, Cheng Y, Hilse M, Engel-Herbert R, Richardella A, Samarth N, Wu M. Changes of Magnetism in a Magnetic Insulator due to Proximity to a Topological Insulator. PHYSICAL REVIEW LETTERS 2020; 125:017204. [PMID: 32678653 DOI: 10.1103/physrevlett.125.017204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 04/13/2020] [Accepted: 06/05/2020] [Indexed: 06/11/2023]
Abstract
We report the modification of magnetism in a magnetic insulator Y_{3}Fe_{5}O_{12} thin film by topological surface states (TSS) in an adjacent topological insulator Bi_{2}Se_{3} thin film. Ferromagnetic resonance measurements show that the TSS in Bi_{2}Se_{3} produces a perpendicular magnetic anisotropy, results in a decrease in the gyromagnetic ratio, and enhances the damping in Y_{3}Fe_{5}O_{12}. Such TSS-induced changes become more pronounced as the temperature decreases from 300 to 50 K. These results suggest a completely new approach for control of magnetism in magnetic thin films.
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Affiliation(s)
- Tao Liu
- Department of Physics, Colorado State University, Fort Collins, Colorado 80523, USA
| | - James Kally
- Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Timothy Pillsbury
- Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Chuanpu Liu
- Department of Physics, Colorado State University, Fort Collins, Colorado 80523, USA
| | - Houchen Chang
- Department of Physics, Colorado State University, Fort Collins, Colorado 80523, USA
| | - Jinjun Ding
- Department of Physics, Colorado State University, Fort Collins, Colorado 80523, USA
| | - Yang Cheng
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA
| | - Maria Hilse
- Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Roman Engel-Herbert
- Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Anthony Richardella
- Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Nitin Samarth
- Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Mingzhong Wu
- Department of Physics, Colorado State University, Fort Collins, Colorado 80523, USA
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8
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Yu T, Bauer GEW. Noncontact Spin Pumping by Microwave Evanescent Fields. PHYSICAL REVIEW LETTERS 2020; 124:236801. [PMID: 32603158 DOI: 10.1103/physrevlett.124.236801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 04/13/2020] [Accepted: 05/20/2020] [Indexed: 06/11/2023]
Abstract
The angular momentum of evanescent light fields has been studied in nano-optics and plasmonics but not in the microwave regime. Here we predict noncontact pumping of electron spin currents in conductors by the evanescent stray fields of excited magnetic nanostructures. The coherent transfer of the photon to the electron spin is proportional to the g factor, which is large in narrow gap semiconductors and surface states of topological insulators. The spin pumping current is chiral when the spin susceptibility displays singularities that indicate collective states. However, 1D systems with linear dispersion at the Fermi energy, such as metallic carbon nanotubes, are an exception since spin pumping is chiral even without interactions.
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Affiliation(s)
- Tao Yu
- Kavli Institute of NanoScience, Delft University of Technology, 2628 CJ Delft, Netherlands
| | - Gerrit E W Bauer
- Kavli Institute of NanoScience, Delft University of Technology, 2628 CJ Delft, Netherlands
- Institute for Materials Research and WPI-AIMR and CSRN, Tohoku University, Sendai 980-8577, Japan
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9
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Dc M, Chen JY, Peterson T, Sahu P, Ma B, Mousavi N, Harjani R, Wang JP. Observation of High Spin-to-Charge Conversion by Sputtered Bismuth Selenide Thin Films at Room Temperature. NANO LETTERS 2019; 19:4836-4844. [PMID: 31283247 DOI: 10.1021/acs.nanolett.8b05011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We investigated spin-to-charge conversion in sputtered Bi43Se57/Co20Fe60B20 heterostructures with in-plane magnetization at room temperature. High spin-to-charge conversion voltage signals have been observed at room temperature. The transmission electron microscope images show that the sputtered bismuth selenide thin films are nanogranular in structure. The spin-pumping voltage decreases with an increase in the size of the grains. The inverse Edelstein effect length (λIEE) is estimated to be as large as 0.32 nm. The large λIEE is due to the spin-momentum locking and is further enhanced by quantum confinement in the nanosized grains of the sputtered bismuth selenide films. We also investigated the effect on spin-pumping voltage due to the insertion of layers of MgO and Ag. The MgO insertion layer has almost completely suppressed the spin-pumping voltage, whereas the Ag insertion layer has enhanced the λIEE by 43%.
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Affiliation(s)
- Mahendra Dc
- School of Physics and Astronomy , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Jun-Yang Chen
- Department of Electrical and Computer Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Thomas Peterson
- School of Physics and Astronomy , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Protuysh Sahu
- School of Physics and Astronomy , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Bin Ma
- Department of Electrical and Computer Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Naser Mousavi
- Department of Electrical and Computer Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Ramesh Harjani
- Department of Electrical and Computer Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Jian-Ping Wang
- School of Physics and Astronomy , University of Minnesota , Minneapolis , Minnesota 55455 , United States
- Department of Electrical and Computer Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
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10
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Che X, Murata K, Pan L, He QL, Yu G, Shao Q, Yin G, Deng P, Fan Y, Ma B, Liang X, Zhang B, Han X, Bi L, Yang QH, Zhang H, Wang KL. Proximity-Induced Magnetic Order in a Transferred Topological Insulator Thin Film on a Magnetic Insulator. ACS NANO 2018; 12:5042-5050. [PMID: 29733577 DOI: 10.1021/acsnano.8b02647] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Breaking the time reversal symmetry (TRS) in a topological insulator (TI) by introducing a magnetic order gives rise to exotic quantum phenomena. One of the promising routes to inducing a magnetic order in a TI is utilizing magnetic proximity effect between a TI and a strong magnetic insulator (MI). In this article, we demonstrate a TI/MI heterostructure prepared through transferring a molecular beam epitaxy (MBE)-grown Bi2Se3 film onto a yttrium iron garnet (YIG) substrate via wet transfer. The transferred Bi2Se3 exhibits excellent quality over a large scale. Moreover, through wet transfer we are able to engineer the interface and perform a comparative study to probe the proximity coupling between Bi2Se3 and YIG under different interface conditions. A detailed investigation of both the anomalous Hall effect and quantum corrections to the conductivity in magnetotransport measurements reveals an induced magnetic order as well as TRS breaking in the transferred Bi2Se3 film on YIG. In contrast, a thin layer of AlO x at the interface obstructs the proximity coupling and preserves the TRS, indicating the critical role of the interface in mediating magnetic proximity effect.
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Affiliation(s)
- Xiaoyu Che
- Department of Electrical and Computer Engineering , University of California , Los Angeles , California 90095 , United States
| | - Koichi Murata
- Department of Electrical and Computer Engineering , University of California , Los Angeles , California 90095 , United States
| | - Lei Pan
- Department of Electrical and Computer Engineering , University of California , Los Angeles , California 90095 , United States
| | - Qing Lin He
- Department of Electrical and Computer Engineering , University of California , Los Angeles , California 90095 , United States
| | - Guoqiang Yu
- Department of Electrical and Computer Engineering , University of California , Los Angeles , California 90095 , United States
- Beijing National Laboratory for Condensed Matter Physics , Institute of Physics, Chinese Academy of Sciences , Beijing 100190 , China
| | - Qiming Shao
- Department of Electrical and Computer Engineering , University of California , Los Angeles , California 90095 , United States
| | - Gen Yin
- Department of Electrical and Computer Engineering , University of California , Los Angeles , California 90095 , United States
| | - Peng Deng
- Department of Electrical and Computer Engineering , University of California , Los Angeles , California 90095 , United States
| | - Yabin Fan
- Department of Electrical and Computer Engineering , University of California , Los Angeles , California 90095 , United States
| | - Bo Ma
- State Key Laboratory of Electronic Thin Film and Integrated Devices , University of Electronic Science and Technology of China , Chengdu 610054 , China
| | - Xiao Liang
- National Engineering Research Center of Electromagnetic Radiation Control Materials , University of Electronic Science and Technology of China , Chengdu 610054 , China
| | - Bin Zhang
- Beijing Key Lab of Microstructure and Property of Advanced Materials , Beijing University of Technology , Beijing 100124 , China
| | - Xiaodong Han
- Beijing Key Lab of Microstructure and Property of Advanced Materials , Beijing University of Technology , Beijing 100124 , China
| | - Lei Bi
- National Engineering Research Center of Electromagnetic Radiation Control Materials , University of Electronic Science and Technology of China , Chengdu 610054 , China
| | - Qing-Hui Yang
- State Key Laboratory of Electronic Thin Film and Integrated Devices , University of Electronic Science and Technology of China , Chengdu 610054 , China
| | - Huaiwu Zhang
- State Key Laboratory of Electronic Thin Film and Integrated Devices , University of Electronic Science and Technology of China , Chengdu 610054 , China
| | - Kang L Wang
- Department of Electrical and Computer Engineering , University of California , Los Angeles , California 90095 , United States
- Department of Materials Science and Engineering , University of California , Los Angeles , California 90095 , United States
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