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Sahoo M, Onuorah IJ, Folkers LC, Kochetkova E, Chulkov EV, Otrokov MM, Aliev ZS, Amiraslanov IR, Wolter AUB, Büchner B, Corredor LT, Wang C, Salman Z, Isaeva A, De Renzi R, Allodi G. Ubiquitous Order-Disorder Transition in the Mn Antisite Sublattice of the (MnBi 2Te 4)(Bi 2Te 3) n Magnetic Topological Insulators. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024:e2402753. [PMID: 38973332 DOI: 10.1002/advs.202402753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 05/22/2024] [Indexed: 07/09/2024]
Abstract
Magnetic topological insulators (TIs) herald a wealth of applications in spin-based technologies, relying on the novel quantum phenomena provided by their topological properties. Particularly promising is the (MnBi2Te4)(Bi2Te3)n layered family of established intrinsic magnetic TIs that can flexibly realize various magnetic orders and topological states. High tunability of this material platform is enabled by manganese-pnictogen intermixing, whose amounts and distribution patterns are controlled by synthetic conditions. Here, nuclear magnetic resonance and muon spin spectroscopy, sensitive local probe techniques, are employed to scrutinize the impact of the intermixing on the magnetic properties of (MnBi2Te4)(Bi2Te3)n and MnSb2Te4. The measurements not only confirm the opposite alignment between the Mn magnetic moments on native sites and antisites in the ground state of MnSb2Te4, but for the first time directly show the same alignment in (MnBi2Te4)(Bi2Te3)n with n = 0, 1 and 2. Moreover, for all compounds, the static magnetic moment of the Mn antisite sublattice is found to disappear well below the intrinsic magnetic transition temperature, leaving a homogeneous magnetic structure undisturbed by the intermixing. The findings provide a microscopic understanding of the crucial role played by Mn-Bi intermixing in (MnBi2Te4)(Bi2Te3)n and offer pathways to optimizing the magnetic gap in its surface states.
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Affiliation(s)
- Manaswini Sahoo
- Leibniz IFW Dresden, Helmholtzstraße 20, D-01069, Dresden, Germany
- Institut für Festkörper- und Materialphysik, Technische Universität Dresden, 01062, Dresden, Germany
- Würzburg-Dresden Cluster of Excellence ct.qmat, Dresden, Germany
- Dipartimento di Scienze Matematiche, Fisiche e Informatiche, Universitá di Parma, Parco delle Scienze 7A, Parma, I-43124, Italy
| | - Ifeanyi John Onuorah
- Dipartimento di Scienze Matematiche, Fisiche e Informatiche, Universitá di Parma, Parco delle Scienze 7A, Parma, I-43124, Italy
| | - Laura Christina Folkers
- Institut für Festkörper- und Materialphysik, Technische Universität Dresden, 01062, Dresden, Germany
- Würzburg-Dresden Cluster of Excellence ct.qmat, Dresden, Germany
| | - Ekaterina Kochetkova
- Institut für Festkörper- und Materialphysik, Technische Universität Dresden, 01062, Dresden, Germany
- Van der Waals-Zeeman Institute, Department of Physics and Astronomy, University of Amsterdam, Science Park 094, Amsterdam, 1098 XH, Netherlands
| | - Evgueni V Chulkov
- Donostia International Physics Center, Sebastián, 20018 Donostia-San, Spain
- Departamento de Polímeros y Materiales Avanzados: Física, Química y Tecnología, Facultad de Ciencias Químicas, Universidad del País Vasco UPV/EHU, Donostia-San Sebastián, 20018, Spain
- Centro de Física de Materiales (CFM-MPC), Centro Mixto (CSIC-UPV/EHU), Donostia-San Sebastián, 20018, Spain
- Saint Petersburg State University, Saint Petersburg, 199034, Russia
| | - Mikhail M Otrokov
- Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC-Universidad de Zaragoza, Zaragoza, 50009, Spain
| | - Ziya S Aliev
- Baku State University, Baku, AZ1148, Azerbaijan
- Institute of Physics Ministry of Science and Education Republic of Azerbaijan, Baku, AZ1143, Azerbaijan
| | - Imamaddin R Amiraslanov
- Baku State University, Baku, AZ1148, Azerbaijan
- Institute of Physics Ministry of Science and Education Republic of Azerbaijan, Baku, AZ1143, Azerbaijan
| | - Anja U B Wolter
- Leibniz IFW Dresden, Helmholtzstraße 20, D-01069, Dresden, Germany
| | - Bernd Büchner
- Leibniz IFW Dresden, Helmholtzstraße 20, D-01069, Dresden, Germany
- Institut für Festkörper- und Materialphysik, Technische Universität Dresden, 01062, Dresden, Germany
- Würzburg-Dresden Cluster of Excellence ct.qmat, Dresden, Germany
| | | | - Chennan Wang
- Laboratory for Muon Spin Spectroscopy, Paul-Scherrer-Institute, Villigen PSI, CH-5232, Switzerland
| | - Zaher Salman
- Laboratory for Muon Spin Spectroscopy, Paul-Scherrer-Institute, Villigen PSI, CH-5232, Switzerland
| | - Anna Isaeva
- Leibniz IFW Dresden, Helmholtzstraße 20, D-01069, Dresden, Germany
- Van der Waals-Zeeman Institute, Department of Physics and Astronomy, University of Amsterdam, Science Park 094, Amsterdam, 1098 XH, Netherlands
- Faculty of Physics, Technical University of Dortmund, Otto-Hahn-Str. 4, 44221, Dortmund, Germany
- Research Center Future Energy Materials and Systems (RC FEMS), Germany
| | - Roberto De Renzi
- Dipartimento di Scienze Matematiche, Fisiche e Informatiche, Universitá di Parma, Parco delle Scienze 7A, Parma, I-43124, Italy
| | - Giuseppe Allodi
- Dipartimento di Scienze Matematiche, Fisiche e Informatiche, Universitá di Parma, Parco delle Scienze 7A, Parma, I-43124, Italy
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Lee Y, Kim C, Son S, Cui J, Park G, Zhang KX, Oh S, Cheong H, Kleibert A, Park JG. Imaging Thermally Fluctuating Néel Vectors in van der Waals Antiferromagnet NiPS 3. NANO LETTERS 2024; 24:6043-6050. [PMID: 38717152 DOI: 10.1021/acs.nanolett.4c00804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2024]
Abstract
Studying antiferromagnetic domains is essential for fundamental physics and potential spintronics applications. Despite their importance, few systematic studies have been performed on antiferromagnet (AFM) domains with high spatial resolution in van der Waals (vdW) materials, and direct probing of the Néel vectors remains challenging. In this work, we found multidomain states in the vdW AFM NiPS3, a material extensively investigated for its unique magnetic exciton. We employed photoemission electron microscopy combined with the X-ray magnetic linear dichroism (XMLD-PEEM) to image the NiPS3's magnetic structure. The nanometer-spatial resolution of XMLD-PEEM allows us to determine local Néel vector orientations and discover thermally fluctuating Néel vectors that are independent of the crystal symmetry even at 65 K, well below the TN of 155 K. We demonstrate that an in-plane orbital moment of the Ni ion is responsible for the weak magnetocrystalline anisotropy. The observed thermal fluctuations of the antiferromagnetic domains may explain the broadening of magnetic exciton peaks at higher temperatures.
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Affiliation(s)
- Youjin Lee
- Center for Quantum Materials, Seoul National University, Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy & Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Chaebin Kim
- Center for Quantum Materials, Seoul National University, Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy & Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Suhan Son
- Center for Quantum Materials, Seoul National University, Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy & Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jingyuan Cui
- Center for Quantum Materials, Seoul National University, Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy & Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Giung Park
- Center for Quantum Materials, Seoul National University, Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy & Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Kai-Xuan Zhang
- Center for Quantum Materials, Seoul National University, Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy & Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Siwon Oh
- Department of Physics, Sogang University, Seoul, 04107, Republic of Korea
| | - Hyeonsik Cheong
- Department of Physics, Sogang University, Seoul, 04107, Republic of Korea
| | - Armin Kleibert
- Swiss Light Source, Paul Scherrer Institut, Villigen, PSI CH-5232, Switzerland
| | - Je-Geun Park
- Center for Quantum Materials, Seoul National University, Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy & Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea
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3
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Qi Y, Kan Y, Li Z. High-resolution imaging of 3D stray-field components with a Fe 3O 4 nanoparticle sensor. NANOSCALE 2024; 16:5164-5168. [PMID: 38369887 DOI: 10.1039/d3nr05437c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Despite rapid advances in magnetic domain imaging techniques, high-resolution imaging of 3D magnetic field components remains a great challenge. Magnetic force microscopy has been utilized to observe the 1D magnetic field component from the sample surface; however, the 1D stray-field component lacks sufficient conditions to clarify the nature of nanomagnetism. Herein, we propose a method for the detection of 3D stray-field components by using a Fe3O4-nanoparticle sensor. We employed this Fe3O4-nanoparticle sensor to detect nanoscale magnetic domains, domain walls, and magnetic vortices (resolution ∼5 nm), and our findings demonstrate its potential in imaging both out-of-plane and in-plane magnetic-field components. Our technique overcomes the limitations of 3D stray-field detection and high-resolution imaging and provides the possibility of observing both out-of-plane and in-plane magnetic field components with a 5 nm resolution, thereby paving the way for the development of future spin-based devices.
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Affiliation(s)
- Yan Qi
- Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission, School of Physics and Materials Engineering, Dalian Minzu University, Dalian, 116600, China.
| | - Yihong Kan
- Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission, School of Physics and Materials Engineering, Dalian Minzu University, Dalian, 116600, China.
| | - Zhenghua Li
- Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission, School of Physics and Materials Engineering, Dalian Minzu University, Dalian, 116600, China.
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4
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Mei R, Zhao YF, Wang C, Ren Y, Xiao D, Chang CZ, Liu CX. Electrically Controlled Anomalous Hall Effect and Orbital Magnetization in Topological Magnet MnBi_{2}Te_{4}. PHYSICAL REVIEW LETTERS 2024; 132:066604. [PMID: 38394580 DOI: 10.1103/physrevlett.132.066604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 12/22/2023] [Indexed: 02/25/2024]
Abstract
We propose an intrinsic mechanism to understand the even-odd effect, namely, opposite signs of anomalous Hall resistance and different shapes of hysteresis loops for even and odd septuple layers (SLs), of MBE-grown MnBi_{2}Te_{4} thin films with electron doping. The nonzero hysteresis loops in the anomalous Hall effect and magnetic circular dichroism for even-SLs MnBi_{2}Te_{4} films originate from two different antiferromagnetic (AFM) configurations with different zeroth Landau level energies of surface states. The complex form of the anomalous Hall hysteresis loop can be understood from two magnetic transitions, a transition between two AFM states followed by a second transition to the ferromagnetic state. Our model also clarifies the relationship and distinction between axion parameter and magnetoelectric coefficient, and shows an even-odd oscillation behavior of magnetoelectric coefficients in MnBi_{2}Te_{4} films.
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Affiliation(s)
- Ruobing Mei
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Yi-Fan Zhao
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Chong Wang
- Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195, USA
| | - Yafei Ren
- Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195, USA
| | - Di Xiao
- Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195, USA
- Department of Physics, University of Washington, Seattle, Washington 98195, USA
| | - Cui-Zu Chang
- 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
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5
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Li S, Liu T, Liu C, Wang Y, Lu HZ, Xie XC. Progress on the antiferromagnetic topological insulator MnBi 2Te 4. Natl Sci Rev 2024; 11:nwac296. [PMID: 38213528 PMCID: PMC10776361 DOI: 10.1093/nsr/nwac296] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Revised: 10/18/2022] [Accepted: 11/09/2022] [Indexed: 01/13/2024] Open
Abstract
Topological materials, which feature robust surface and/or edge states, have now been a research focus in condensed matter physics. They represent a new class of materials exhibiting nontrivial topological phases, and provide a platform for exploring exotic transport phenomena, such as the quantum anomalous Hall effect and the quantum spin Hall effect. Recently, magnetic topological materials have attracted considerable interests due to the possibility to study the interplay between topological and magnetic orders. In particular, the quantum anomalous Hall and axion insulator phases can be realized in topological insulators with magnetic order. MnBi2Te4, as the first intrinsic antiferromagnetic topological insulator discovered, allows the examination of existing theoretical predictions; it has been extensively studied, and many new discoveries have been made. Here we review the progress made on MnBi2Te4 from both experimental and theoretical aspects. The bulk crystal and magnetic structures are surveyed first, followed by a review of theoretical calculations and experimental probes on the band structure and surface states, and a discussion of various exotic phases that can be realized in MnBi2Te4. The properties of MnBi2Te4 thin films and the corresponding transport studies are then reviewed, with an emphasis on the edge state transport. Possible future research directions in this field are also discussed.
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Affiliation(s)
- Shuai Li
- Department of Physics, Harbin Institute of Technology, Harbin 150001, China
- Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
- Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area (Guangdong), Shenzhen 518045, China
- Shenzhen Key Laboratory of Quantum Science and Engineering, Shenzhen 518055, China
- International Quantum Academy, Shenzhen 518048, China
| | - Tianyu Liu
- Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
- Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area (Guangdong), Shenzhen 518045, China
- Shenzhen Key Laboratory of Quantum Science and Engineering, Shenzhen 518055, China
- International Quantum Academy, Shenzhen 518048, China
| | - Chang Liu
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-Nano Devices, Department of Physics, Renmin University of China, Beijing 100872, China
| | - Yayu Wang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Beijing 100084, China
- Hefei National Laboratory, Hefei 230088, China
| | - Hai-Zhou Lu
- Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
- Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area (Guangdong), Shenzhen 518045, China
- Shenzhen Key Laboratory of Quantum Science and Engineering, Shenzhen 518055, China
- International Quantum Academy, Shenzhen 518048, China
| | - X C Xie
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
- Institute for Nanoelectronic Devices and Quantum Computing, Fudan University, Shanghai 200433, China
- Hefei National Laboratory, Hefei 230088, China
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6
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Bai Y, Li Y, Luan J, Liu R, Song W, Chen Y, Ji PF, Zhang Q, Meng F, Tong B, Li L, Jiang Y, Gao Z, Gu L, Zhang J, Wang Y, Xue QK, He K, Feng Y, Feng X. Quantized anomalous Hall resistivity achieved in molecular beam epitaxy-grown MnBi 2Te 4 thin films. Natl Sci Rev 2024; 11:nwad189. [PMID: 38213514 PMCID: PMC10776363 DOI: 10.1093/nsr/nwad189] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 04/29/2023] [Accepted: 05/16/2023] [Indexed: 01/13/2024] Open
Abstract
The intrinsic magnetic topological insulator MnBi2Te4 provides a feasible pathway to the high-temperature quantum anomalous Hall (QAH) effect as well as various novel topological quantum phases. Although quantized transport properties have been observed in exfoliated MnBi2Te4 thin flakes, it remains a big challenge to achieve molecular beam epitaxy (MBE)-grown MnBi2Te4 thin films even close to the quantized regime. In this work, we report the realization of quantized anomalous Hall resistivity in MBE-grown MnBi2Te4 thin films with the chemical potential tuned by both controlled in situ oxygen exposure and top gating. We find that elongated post-annealing obviously elevates the temperature to achieve quantization of the Hall resistivity, but also increases the residual longitudinal resistivity, indicating a picture of high-quality QAH puddles weakly coupled by tunnel barriers. These results help to clarify the puzzles in previous experimental studies on MnBi2Te4 and to find a way out of the big difficulty in obtaining MnBi2Te4 samples showing quantized transport properties.
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Affiliation(s)
- Yunhe Bai
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing100084, China
| | - Yuanzhao Li
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing100084, China
| | - Jianli Luan
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing100084, China
| | - Ruixuan Liu
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing100084, China
| | - Wenyu Song
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing100084, China
| | - Yang Chen
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing100084, China
| | - Peng-Fei Ji
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing100084, China
| | - Qinghua Zhang
- Institute of Physics, Chinese Academy of Sciences, Beijing100190, China
| | - Fanqi Meng
- School of Materials Science and Engineering, Tsinghua University, Beijing100084, China
| | - Bingbing Tong
- Beijing Academy of Quantum Information Sciences, Beijing100193, China
| | - Lin Li
- Beijing Academy of Quantum Information Sciences, Beijing100193, China
| | - Yuying Jiang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing100084, China
| | - Zongwei Gao
- Beijing Academy of Quantum Information Sciences, Beijing100193, China
| | - Lin Gu
- School of Materials Science and Engineering, Tsinghua University, Beijing100084, China
| | - Jinsong Zhang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing100084, China
- Frontier Science Center for Quantum Information, Beijing100084, China
- Hefei National Laboratory, Hefei230088, China
| | - Yayu Wang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing100084, China
- Frontier Science Center for Quantum Information, Beijing100084, China
- Hefei National Laboratory, Hefei230088, China
| | - Qi-Kun Xue
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing100084, China
- Frontier Science Center for Quantum Information, Beijing100084, China
- Beijing Academy of Quantum Information Sciences, Beijing100193, China
- Southern University of Science and Technology, Shenzhen518055, China
| | - Ke He
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing100084, China
- Frontier Science Center for Quantum Information, Beijing100084, China
- Beijing Academy of Quantum Information Sciences, Beijing100193, China
- Hefei National Laboratory, Hefei230088, China
| | - Yang Feng
- Beijing Academy of Quantum Information Sciences, Beijing100193, China
| | - Xiao Feng
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing100084, China
- Frontier Science Center for Quantum Information, Beijing100084, China
- Beijing Academy of Quantum Information Sciences, Beijing100193, China
- Hefei National Laboratory, Hefei230088, China
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7
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Wang Y, Ma XM, Hao Z, Cai Y, Rong H, Zhang F, Chen W, Zhang C, Lin J, Zhao Y, Liu C, Liu Q, Chen C. On the topological surface states of the intrinsic magnetic topological insulator Mn-Bi-Te family. Natl Sci Rev 2024; 11:nwad066. [PMID: 38213518 PMCID: PMC10776371 DOI: 10.1093/nsr/nwad066] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 12/12/2022] [Accepted: 01/03/2023] [Indexed: 01/13/2024] Open
Abstract
We review recent progress in the electronic structure study of intrinsic magnetic topological insulators (MnBi2Te4) · (Bi2Te3)n ([Formula: see text]) family. Specifically, we focus on the ubiquitously (nearly) gapless behavior of the topological Dirac surface state observed by photoemission spectroscopy, even though a large Dirac gap is expected because of surface ferromagnetic order. The dichotomy between experiment and theory concerning this gap behavior is perhaps the most critical and puzzling question in this frontier. We discuss various proposals accounting for the lack of magnetic effect on the topological Dirac surface state, which are mainly categorized into two pictures, magnetic reconfiguration and topological surface state redistribution. Band engineering towards opening a magnetic gap of topological surface states provides great opportunities to realize quantized topological transport and axion electrodynamics at higher temperatures.
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Affiliation(s)
- Yuan Wang
- Shenzhen Institute for Quantum Science and Engineering (SIQSE) and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Xiao-Ming Ma
- Shenzhen Institute for Quantum Science and Engineering (SIQSE) and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Zhanyang Hao
- Shenzhen Institute for Quantum Science and Engineering (SIQSE) and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Yongqing Cai
- Shenzhen Institute for Quantum Science and Engineering (SIQSE) and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Hongtao Rong
- Shenzhen Institute for Quantum Science and Engineering (SIQSE) and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Fayuan Zhang
- Shenzhen Institute for Quantum Science and Engineering (SIQSE) and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Weizhao Chen
- Shenzhen Institute for Quantum Science and Engineering (SIQSE) and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Chengcheng Zhang
- Shenzhen Institute for Quantum Science and Engineering (SIQSE) and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Junhao Lin
- Shenzhen Institute for Quantum Science and Engineering (SIQSE) and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Yue Zhao
- Shenzhen Institute for Quantum Science and Engineering (SIQSE) and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Chang Liu
- Shenzhen Institute for Quantum Science and Engineering (SIQSE) and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Qihang Liu
- Shenzhen Institute for Quantum Science and Engineering (SIQSE) and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Chaoyu Chen
- Shenzhen Institute for Quantum Science and Engineering (SIQSE) and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
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8
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Xu R, Xu L, Liu Z, Yang L, Chen Y. ARPES investigation of the electronic structure and its evolution in magnetic topological insulator MnBi 2+2nTe 4+3n family. Natl Sci Rev 2024; 11:nwad313. [PMID: 38327664 PMCID: PMC10849349 DOI: 10.1093/nsr/nwad313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 11/14/2023] [Accepted: 11/19/2023] [Indexed: 02/09/2024] Open
Abstract
In the past 5 years, there has been significant research interest in the intrinsic magnetic topological insulator family compounds MnBi2+2nTe4+3n (where n = 0, 1, 2 …). In particular, exfoliated thin films of MnBi2Te4 have led to numerous experimental breakthroughs, such as the quantum anomalous Hall effect, axion insulator phase and high-Chern number quantum Hall effect without Landau levels. However, despite extensive efforts, the energy gap of the topological surface states due to exchange magnetic coupling, which is a key feature of the characteristic band structure of the system, remains experimentally elusive. The electronic structure measured by using angle-resolved photoemission (ARPES) shows significant deviation from ab initio prediction and scanning tunneling spectroscopy measurements, making it challenging to understand the transport results based on the electronic structure. This paper reviews the measurements of the band structure of MnBi2+2nTe4+3n magnetic topological insulators using ARPES, focusing on the evolution of their electronic structures with temperature, surface and bulk doping and film thickness. The aim of the review is to construct a unified picture of the electronic structure of MnBi2+2nTe4+3n compounds and explore possible control of their topological properties.
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Affiliation(s)
- Runzhe Xu
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Lixuan Xu
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- School of Physical Science and Technology, ShanghaiTech University and CAS-Shanghai Science Research Center, Shanghai 201210, China
| | - Zhongkai Liu
- School of Physical Science and Technology, ShanghaiTech University and CAS-Shanghai Science Research Center, Shanghai 201210, China
- ShanghaiTech Laboratory for Topological Physics, Shanghai 200031, China
| | - Lexian Yang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Beijing 100084, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
| | - Yulin Chen
- School of Physical Science and Technology, ShanghaiTech University and CAS-Shanghai Science Research Center, Shanghai 201210, China
- ShanghaiTech Laboratory for Topological Physics, Shanghai 200031, China
- Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, UK
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9
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Andersen MP, Mikheev E, Rosen IT, Tai L, Zhang P, Wang KL, Kastner MA, Goldhaber-Gordon D. Universal Conductance Fluctuations in a MnBi 2Te 4 Thin Film. NANO LETTERS 2023. [PMID: 38029283 DOI: 10.1021/acs.nanolett.3c02932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2023]
Abstract
Quantum coherence of electrons can produce striking behaviors in mesoscopic conductors. Although magnetic order can also strongly affect transport, the combination of coherence and magnetic order has been largely unexplored. Here, we examine quantum coherence-driven universal conductance fluctuations in the antiferromagnetic, canted antiferromagnetic, and ferromagnetic phases of a thin film of the topological material MnBi2Te4. In each magnetic phase, we extract a charge carrier phase coherence length of about 100 nm. The conductance magnetofingerprint is repeatable when sweeping applied magnetic field within one magnetic phase. Surprisingly, in the antiferromagnetic and canted antiferromagnetic phases, but not in the ferromagnetic phase, the magnetofingerprint depends on the direction of the field sweep. To explain our observations, we suggest that conductance fluctuation measurements are sensitive to the motion and nucleation of magnetic domain walls in MnBi2Te4.
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Affiliation(s)
- Molly P Andersen
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
- Department of Physics, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Evgeny Mikheev
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
- Department of Physics, Stanford University, Stanford, California 94305, United States
- Department of Physics, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Ilan T Rosen
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
- Department of Physics, University of Cincinnati, Cincinnati, Ohio 45221, United States
- Department of Applied Physics, Stanford University, Stanford, California 94305, United States
- Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Lixuan Tai
- Department of Electrical and Computer Engineering, University of California, Los Angeles, Los Angeles, California 90095, United States
| | - Peng Zhang
- Department of Electrical and Computer Engineering, University of California, Los Angeles, Los Angeles, California 90095, United States
| | - Kang L Wang
- Department of Electrical and Computer Engineering, University of California, Los Angeles, Los Angeles, California 90095, United States
| | - Marc A Kastner
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
- Department of Physics, Stanford University, Stanford, California 94305, United States
- Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - David Goldhaber-Gordon
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
- Department of Physics, Stanford University, Stanford, California 94305, United States
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10
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Deng H, Zhang Y, Yang X, Yu Q, Wang P, Yang Z, Dai Y, Pang X, Wang X, Wu J, Zhou P. Magnetic Topological Insulator MnBi 2Te 4 Nanosheets for Femtosecond Pulse Generation. ACS APPLIED MATERIALS & INTERFACES 2023; 15:47250-47259. [PMID: 37751475 DOI: 10.1021/acsami.3c09544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/28/2023]
Abstract
The van der Waals layered material MnBi2Te4, as a magnetic topological insulator, has attracted tremendous interest for novel physics research in the fields of condensed matter physics and materials science. However, the nonlinear optical properties of MnBi2Te4 and its applications in ultrafast optics have rarely been explored. In this study, high-quality MnBi2Te4 nanosheets have been successfully synthesized by the self-flux method. The morphology, chemical composition, magnetic properties, and nonlinear optical characteristics were systematically investigated. The magnetic transition of MnBi2Te4 was confirmed by a low-temperature spatially resolved spectroscopic technique. The saturable absorption property of MnBi2Te4 was measured by a balanced twin-detector system with a modulation depth of 4.5% and a saturation optical intensity of 2.35 GW/cm2. Furthermore, by inserting the MnBi2Te4-based saturable absorber, a soliton mode-locking laser operating at 1558.8 nm was obtained with a pulse duration of 331 fs. This research will pave the way for applications of the magnetic TI MnBi2Te4 in nonlinear optics and photonics.
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Affiliation(s)
- Haiqin Deng
- College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China
| | - Yan Zhang
- i-Lab & Key Laboratory of Nanodevices and Applications & Key Laboratory of Nanophotonic Materials and Devices, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215125, China
| | - Xiaoxin Yang
- Institute of Technology for Carbon Neutrality, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, Guangdong, China
| | - Qiang Yu
- College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China
- i-Lab & Key Laboratory of Nanodevices and Applications & Key Laboratory of Nanophotonic Materials and Devices, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215125, China
| | - Pengdong Wang
- Vacuum Interconnected Nanotech Workstation, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences (CAS), Suzhou 215123, China
| | - Zixin Yang
- College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China
| | - Yongping Dai
- i-Lab & Key Laboratory of Nanodevices and Applications & Key Laboratory of Nanophotonic Materials and Devices, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215125, China
- Engineering Research Center of Advanced Rare Earth Materials (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Xiuyang Pang
- College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China
| | - Xiao Wang
- Institute of Technology for Carbon Neutrality, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, Guangdong, China
| | - Jian Wu
- College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China
| | - Pu Zhou
- College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China
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11
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Chong SK, Lei C, Lee SH, Jaroszynski J, Mao Z, MacDonald AH, Wang KL. Anomalous Landau quantization in intrinsic magnetic topological insulators. Nat Commun 2023; 14:4805. [PMID: 37558682 PMCID: PMC10412595 DOI: 10.1038/s41467-023-40383-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 07/21/2023] [Indexed: 08/11/2023] Open
Abstract
The intrinsic magnetic topological insulator, Mn(Bi1-xSbx)2Te4, has been identified as a Weyl semimetal with a single pair of Weyl nodes in its spin-aligned strong-field configuration. A direct consequence of the Weyl state is the layer dependent Chern number, [Formula: see text]. Previous reports in MnBi2Te4 thin films have shown higher [Formula: see text] states either by increasing the film thickness or controlling the chemical potential. A clear picture of the higher Chern states is still lacking as data interpretation is further complicated by the emergence of surface-band Landau levels under magnetic fields. Here, we report a tunable layer-dependent [Formula: see text] = 1 state with Sb substitution by performing a detailed analysis of the quantization states in Mn(Bi1-xSbx)2Te4 dual-gated devices-consistent with calculations of the bulk Weyl point separation in the doped thin films. The observed Hall quantization plateaus for our thicker Mn(Bi1-xSbx)2Te4 films under strong magnetic fields can be interpreted by a theory of surface and bulk spin-polarised Landau level spectra in thin film magnetic topological insulators.
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Affiliation(s)
- Su Kong Chong
- Department of Electrical and Computer Engineering, University of California, Los Angeles, CA, 90095, USA.
| | - Chao Lei
- Department of Physics, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Seng Huat Lee
- 2D Crystal Consortium, Materials Research Institute, The Pennsylvania State University, University Park, PA, 16802, USA
- Department of Physics, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Jan Jaroszynski
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL, USA
| | - Zhiqiang Mao
- 2D Crystal Consortium, Materials Research Institute, The Pennsylvania State University, University Park, PA, 16802, USA
- Department of Physics, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Allan H MacDonald
- Department of Physics, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Kang L Wang
- Department of Electrical and Computer Engineering, University of California, Los Angeles, CA, 90095, USA.
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12
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Rahman MM, Rustagi A, Tserkovnyak Y, Upadhyaya P. Electrically Active Domain Wall Magnons in Layered van der Waals Antiferromagnets. PHYSICAL REVIEW LETTERS 2023; 130:036701. [PMID: 36763400 DOI: 10.1103/physrevlett.130.036701] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 10/26/2022] [Accepted: 12/06/2022] [Indexed: 06/18/2023]
Abstract
We study, theoretically, domain wall (DW) magnons-elementary collective excitations of magnetic DWs-in easy-axis layered van der Waals (vdW) antiferromagnets, where they behave as normal modes of coupled spin superfluids. We uncover that, due to spin-charge coupling in vdW magnets, such DW magnons can be activated by voltage-induced torques, thereby providing a path for their low-dissipation and nanoscale excitation. Moreover, the electrical activation and the number of DW magnons at a frequency can be controlled by applying symmetry-breaking static magnetic field, adding tunability of signal transmission by them. Our results highlight that domain walls in vdW magnets provide a promising platform to route coherent spin information for a broad range of explorations in spintronics and magnetism.
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Affiliation(s)
- Mohammad Mushfiqur Rahman
- Elmore Family School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907, USA
| | - Avinash Rustagi
- Elmore Family School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907, USA
| | - Yaroslav Tserkovnyak
- Department of Physics and Astronomy, University of California, Los Angeles, California 90095, USA
| | - Pramey Upadhyaya
- Elmore Family School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907, USA
- Purdue Quantum Science and Engineering Institute, Purdue University, West Lafayette, Indiana 47907, USA
- Quantum Science Center, Oak Ridge, Tennessee 37831, USA
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13
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Xu Z, Duan W, Xu Y. Controllable Chirality and Band Gap of Quantum Anomalous Hall Insulators. NANO LETTERS 2023; 23:305-311. [PMID: 36537751 DOI: 10.1021/acs.nanolett.2c04369] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Finding guiding principles to optimize properties of quantum anomalous Hall (QAH) insulators is of pivotal importance to fundamental science and applications. Here, we build a first-principles QAH material database of chirality and band gap, explore microscopic mechanisms determining the QAH material properties, and obtain a general physical picture that can help researchers comprehensively understand the QAH data. Our results reveal that the usually neglected Coulomb exchange is unexpectedly strong in a large class of QAH materials, which is the key to resolve experimental puzzles. Moreover, we identify simple indicators for property evaluation and suggest material design strategies to control QAH chirality and gap by tuning cooperative or competing contributions via magnetic codoping, heterostructuring, spin-orbit proximity, etc. The work is valuable to future research of magnetic topological physics and materials.
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Affiliation(s)
- Zhiming Xu
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing100084, China
| | - Wenhui Duan
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing100084, China
- Tencent Quantum Laboratory, Tencent, Shenzhen, Guangdong518057, China
- Frontier Science Center for Quantum Information, Beijing100084, China
- Collaborative Innovation Center of Quantum Matter, Beijing100084, China
- Institute for Advanced Study, Tsinghua University, Beijing100084, China
- Beijing Academy of Quantum Information Sciences, Beijing100193, China
| | - Yong Xu
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing100084, China
- Tencent Quantum Laboratory, Tencent, Shenzhen, Guangdong518057, China
- Frontier Science Center for Quantum Information, Beijing100084, China
- Collaborative Innovation Center of Quantum Matter, Beijing100084, China
- RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama351-0198, Japan
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14
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Padmanabhan H, Stoica VA, Kim PK, Poore M, Yang T, Shen X, Reid AH, Lin MF, Park S, Yang J, Wang HH, Koocher NZ, Puggioni D, Georgescu AB, Min L, Lee SH, Mao Z, Rondinelli JM, Lindenberg AM, Chen LQ, Wang X, Averitt RD, Freeland JW, Gopalan V. Large Exchange Coupling Between Localized Spins and Topological Bands in MnBi 2 Te 4. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2202841. [PMID: 36189841 DOI: 10.1002/adma.202202841] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 09/21/2022] [Indexed: 06/16/2023]
Abstract
Magnetism in topological materials creates phases exhibiting quantized transport phenomena with potential technological applications. The emergence of such phases relies on strong interaction between localized spins and the topological bands, and the consequent formation of an exchange gap. However, this remains experimentally unquantified in intrinsic magnetic topological materials. Here, this interaction is quantified in MnBi2 Te4 , a topological insulator with intrinsic antiferromagnetism. This is achieved by optically exciting Bi-Te p states comprising the bulk topological bands and interrogating the consequent Mn 3d spin dynamics, using a multimodal ultrafast approach. Ultrafast electron scattering and magneto-optic measurements show that the p states demagnetize via electron-phonon scattering at picosecond timescales. Despite being energetically decoupled from the optical excitation, the Mn 3d spins, probed by resonant X-ray scattering, are observed to disorder concurrently with the p spins. Together with atomistic simulations, this reveals that the exchange coupling between localized spins and the topological bands is at least 100 times larger than the superexchange interaction, implying an optimal exchange gap of at least 25 meV in the surface states. By quantifying this exchange coupling, this study validates the materials-by-design strategy of utilizing localized magnetic order to manipulate topological phases, spanning static to ultrafast timescales.
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Affiliation(s)
- Hari Padmanabhan
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Vladimir A Stoica
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Peter K Kim
- Department of Physics, University of California San Diego, La Jolla, CA, 92093, USA
| | - Maxwell Poore
- Department of Physics, University of California San Diego, La Jolla, CA, 92093, USA
| | - Tiannan Yang
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Xiaozhe Shen
- SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, USA
| | - Alexander H Reid
- SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, USA
| | - Ming-Fu Lin
- SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, USA
| | - Suji Park
- SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, USA
| | - Jie Yang
- SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, USA
| | - Huaiyu Hugo Wang
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Nathan Z Koocher
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Danilo Puggioni
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Alexandru B Georgescu
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Lujin Min
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Seng Huat Lee
- 2D Crystal Consortium, Materials Research Institute, The Pennsylvania State University, University Park, PA, 16802, USA
- Department of Physics, Penn State University, University Park, PA, 16802, USA
| | - Zhiqiang Mao
- 2D Crystal Consortium, Materials Research Institute, The Pennsylvania State University, University Park, PA, 16802, USA
- Department of Physics, Penn State University, University Park, PA, 16802, USA
| | - James M Rondinelli
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Aaron M Lindenberg
- SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, USA
- Department of Materials Science and Engineering, Stanford University, Menlo Park, CA, 94305, USA
| | - Long-Qing Chen
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Xijie Wang
- SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, USA
| | - Richard D Averitt
- Department of Physics, University of California San Diego, La Jolla, CA, 92093, USA
| | - John W Freeland
- X-ray Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Venkatraman Gopalan
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
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15
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Ge W, Kim J, Chan YT, Vanderbilt D, Yan J, Wu W. Direct Visualization of Surface Spin-Flip Transition in MnBi_{4}Te_{7}. PHYSICAL REVIEW LETTERS 2022; 129:107204. [PMID: 36112444 DOI: 10.1103/physrevlett.129.107204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 06/23/2022] [Accepted: 08/09/2022] [Indexed: 06/15/2023]
Abstract
We report direct visualization of spin-flip transition of the surface layer in antiferromagnet MnBi_{4}Te_{7}, a natural superlattice of alternating MnBi_{2}Te_{4} and Bi_{2}Te_{3} layers, using cryogenic magnetic force microscopy (MFM). The observation of magnetic contrast across domain walls and step edges confirms that the antiferromagnetic order persists to the surface layers. The magnetic field dependence of the MFM images reveals that the surface magnetic layer undergoes a first-order spin-flip transition at a magnetic field that is lower than the bulk transition, in excellent agreement with a revised Mills model. Our analysis suggests no reduction of the order parameter in the surface magnetic layer, implying robust ferromagnetism in the single-layer limit. The direct visualization of surface spin-flip transition not only opens up exploration of surface metamagnetic transitions in layered antiferromagnets, but also provides experimental support for realizing quantized transport in ultrathin films of MnBi_{4}Te_{7} and other natural superlattice topological magnets.
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Affiliation(s)
- Wenbo Ge
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Jinwoong Kim
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Ying-Ting Chan
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Jiaqiang Yan
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Weida Wu
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
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16
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Choi T, Zhang Z, Kim H, Park S, Kim JW, Lee KJ, Islam Z, Welp U, Chang SH, Kim BJ. Nanoscale Antiferromagnetic Domain Imaging using Full-Field Resonant X-ray Magnetic Diffraction Microscopy. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2200639. [PMID: 35580279 DOI: 10.1002/adma.202200639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 05/12/2022] [Indexed: 06/15/2023]
Abstract
The physical properties of magnetic materials frequently depend not only on the microscopic spin and electronic structures, but also on the structures of mesoscopic length scales that emerge, for instance, from domain formations, or chemical and/or electronic phase separations. However, experimental access to such mesoscopic structures is currently limited, especially for antiferromagnets with net zero magnetization. Here, full-field microscopy and resonant magnetic X-ray diffraction are combined to visualize antiferromagnetic (AF) domains of the spin-orbit Mott insulator Sr2 IrO4 with area over ≈0.1 mm2 and with spatial resolution as high as ≈150 nm. With the unprecedented wide field of views and high spatial resolution, an intertwining of two AF domains on a length comparable to the measured average AF domain wall width of 545 nm is revealed. This mesoscopic structure comprises a substantial portion of the sample surface, and thus can result in a macroscopic response unexpected from its microscopic magnetic structure. In particular, the symmetry analysis presented in this work shows that the inversion symmetry, which is preserved by the microscopic AF order, becomes ill-defined at the mesoscopic length scale. This result underscores the importance of this novel technique for a thorough understanding of the physical properties of antiferromagnets.
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Affiliation(s)
- Taeyang Choi
- Department of Physics, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - Zhan Zhang
- Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Hoon Kim
- Department of Physics, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), 77 Cheongam-Ro, Pohang, 37673, Republic of Korea
| | - Sunwook Park
- Department of Physics, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), 77 Cheongam-Ro, Pohang, 37673, Republic of Korea
| | - Jong-Woo Kim
- Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Kyeong Jun Lee
- Department of Physics, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - Zahir Islam
- Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Ulrich Welp
- Materials Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Seo Hyoung Chang
- Department of Physics, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - B J Kim
- Department of Physics, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), 77 Cheongam-Ro, Pohang, 37673, Republic of Korea
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17
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Rizzo DJ, McLeod AS, Carnahan C, Telford EJ, Dismukes AH, Wiscons RA, Dong Y, Nuckolls C, Dean CR, Pasupathy AN, Roy X, Xiao D, Basov DN. Visualizing Atomically Layered Magnetism in CrSBr. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2201000. [PMID: 35504841 DOI: 10.1002/adma.202201000] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 04/22/2022] [Indexed: 06/14/2023]
Abstract
2D materials can host long-range magnetic order in the presence of underlying magnetic anisotropy. The ability to realize the full potential of 2D magnets necessitates systematic investigation of the role of individual atomic layers and nanoscale inhomogeneity (i.e., strain) on the emergence of stable magnetic phases. Here, spatially dependent magnetism in few-layer CrSBr is revealed using magnetic force microscopy (MFM) and Monte Carlo-based simulations. Nanoscale visualization of the magnetic sheet susceptibility is extracted from MFM data and force-distance curves, revealing a characteristic onset of both intra- and interlayer magnetic correlations as a function of temperature and layer-thickness. These results demonstrate that the presence of a single uncompensated layer in odd-layer terraces significantly reduces the stability of the low-temperature antiferromagnetic (AFM) phase and gives rise to multiple coexisting magnetic ground states at temperatures close to the bulk Néel temperature (TN ). Furthermore, the AFM phase can be reliably suppressed using modest fields (≈16 mT) from the MFM probe, behaving as a nanoscale magnetic switch. This prototypical study of few-layer CrSBr demonstrates the critical role of layer parity on field-tunable 2D magnetism and validates MFM for use in nanomagnetometry of 2D materials (despite the ubiquitous absence of bulk zero-field magnetism in magnetized sheets).
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Affiliation(s)
- Daniel J Rizzo
- Department of Physics, Columbia University, New York, NY, 10027, USA
| | | | - Caitlin Carnahan
- Department of Physics, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Evan J Telford
- Department of Physics, Columbia University, New York, NY, 10027, USA
- Department of Chemistry, Columbia University, New York, NY, 10027, USA
| | - Avalon H Dismukes
- Department of Chemistry, Columbia University, New York, NY, 10027, USA
| | - Ren A Wiscons
- Department of Chemistry, Columbia University, New York, NY, 10027, USA
| | - Yinan Dong
- Department of Physics, Columbia University, New York, NY, 10027, USA
| | - Colin Nuckolls
- Department of Chemistry, Columbia University, New York, NY, 10027, USA
| | - Cory R Dean
- Department of Physics, Columbia University, New York, NY, 10027, USA
| | - Abhay N Pasupathy
- Department of Physics, Columbia University, New York, NY, 10027, USA
| | - Xavier Roy
- Department of Chemistry, Columbia University, New York, NY, 10027, USA
| | - Di Xiao
- Department of Material Science and Engineering, University of Washington, Seattle, WA, 98195, USA
- Department of Physics, University of Washington, Seattle, WA, 98195, USA
| | - D N Basov
- Department of Physics, Columbia University, New York, NY, 10027, USA
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18
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Wang QH, Bedoya-Pinto A, Blei M, Dismukes AH, Hamo A, Jenkins S, Koperski M, Liu Y, Sun QC, Telford EJ, Kim HH, Augustin M, Vool U, Yin JX, Li LH, Falin A, Dean CR, Casanova F, Evans RFL, Chshiev M, Mishchenko A, Petrovic C, He R, Zhao L, Tsen AW, Gerardot BD, Brotons-Gisbert M, Guguchia Z, Roy X, Tongay S, Wang Z, Hasan MZ, Wrachtrup J, Yacoby A, Fert A, Parkin S, Novoselov KS, Dai P, Balicas L, Santos EJG. The Magnetic Genome of Two-Dimensional van der Waals Materials. ACS NANO 2022; 16:6960-7079. [PMID: 35442017 PMCID: PMC9134533 DOI: 10.1021/acsnano.1c09150] [Citation(s) in RCA: 70] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 02/23/2022] [Indexed: 05/23/2023]
Abstract
Magnetism in two-dimensional (2D) van der Waals (vdW) materials has recently emerged as one of the most promising areas in condensed matter research, with many exciting emerging properties and significant potential for applications ranging from topological magnonics to low-power spintronics, quantum computing, and optical communications. In the brief time after their discovery, 2D magnets have blossomed into a rich area for investigation, where fundamental concepts in magnetism are challenged by the behavior of spins that can develop at the single layer limit. However, much effort is still needed in multiple fronts before 2D magnets can be routinely used for practical implementations. In this comprehensive review, prominent authors with expertise in complementary fields of 2D magnetism (i.e., synthesis, device engineering, magneto-optics, imaging, transport, mechanics, spin excitations, and theory and simulations) have joined together to provide a genome of current knowledge and a guideline for future developments in 2D magnetic materials research.
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Affiliation(s)
- Qing Hua Wang
- Materials
Science and Engineering, School for Engineering of Matter, Transport
and Energy, Arizona State University, Tempe, Arizona 85287, United States
| | - Amilcar Bedoya-Pinto
- NISE
Department, Max Planck Institute of Microstructure
Physics, 06120 Halle, Germany
- Instituto
de Ciencia Molecular (ICMol), Universitat
de València, 46980 Paterna, Spain
| | - Mark Blei
- Materials
Science and Engineering, School for Engineering of Matter, Transport
and Energy, Arizona State University, Tempe, Arizona 85287, United States
| | - Avalon H. Dismukes
- Department
of Chemistry, Columbia University, New York, New York 10027, United States
| | - Assaf Hamo
- Department
of Physics, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Sarah Jenkins
- Twist
Group,
Faculty of Physics, University of Duisburg-Essen, Campus Duisburg, 47057 Duisburg, Germany
| | - Maciej Koperski
- Institute
for Functional Intelligent Materials, National
University of Singapore, 117544 Singapore
| | - Yu Liu
- Condensed
Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Qi-Chao Sun
- Physikalisches
Institut, University of Stuttgart, 70569 Stuttgart, Germany
| | - Evan J. Telford
- Department
of Chemistry, Columbia University, New York, New York 10027, United States
- Department
of Physics, Columbia University, New York, New York 10027, United States
| | - Hyun Ho Kim
- School
of Materials Science and Engineering, Department of Energy Engineering
Convergence, Kumoh National Institute of
Technology, Gumi 39177, Korea
| | - Mathias Augustin
- Institute
for Condensed Matter Physics and Complex Systems, School of Physics
and Astronomy, The University of Edinburgh, Edinburgh, EH9 3FD, United Kingdom
- Donostia
International Physics Center (DIPC), 20018 Donostia-San Sebastián, Basque Country, Spain
| | - Uri Vool
- Department
of Physics, Harvard University, Cambridge, Massachusetts 02138, United States
- John Harvard
Distinguished Science Fellows Program, Harvard
University, Cambridge, Massachusetts 02138, United States
| | - Jia-Xin Yin
- Laboratory
for Topological Quantum Matter and Spectroscopy, Department of Physics, Princeton University, Princeton, New Jersey 08544, United States
| | - Lu Hua Li
- Institute
for Frontier Materials, Deakin University, Geelong Waurn Ponds Campus, Waurn Ponds, Victoria 3216, Australia
| | - Alexey Falin
- Institute
for Frontier Materials, Deakin University, Geelong Waurn Ponds Campus, Waurn Ponds, Victoria 3216, Australia
| | - Cory R. Dean
- Department
of Physics, Columbia University, New York, New York 10027, United States
| | - Fèlix Casanova
- CIC nanoGUNE
BRTA, 20018 Donostia - San Sebastián, Basque
Country, Spain
- IKERBASQUE,
Basque Foundation for Science, 48013 Bilbao, Basque Country, Spain
| | - Richard F. L. Evans
- Department
of Physics, University of York, Heslington, York YO10 5DD, United Kingdom
| | - Mairbek Chshiev
- Université
Grenoble Alpes, CEA, CNRS, Spintec, 38000 Grenoble, France
- Institut
Universitaire de France, 75231 Paris, France
| | - Artem Mishchenko
- Department
of Physics and Astronomy, University of
Manchester, Manchester, M13 9PL, United Kingdom
- National
Graphene Institute, University of Manchester, Manchester, M13 9PL, United Kingdom
| | - Cedomir Petrovic
- Condensed
Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Rui He
- Department
of Electrical and Computer Engineering, Texas Tech University, 910 Boston Avenue, Lubbock, Texas 79409, United
States
| | - Liuyan Zhao
- Department
of Physics, University of Michigan, 450 Church Street, Ann Arbor, Michigan 48109, United States
| | - Adam W. Tsen
- Institute
for Quantum Computing and Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Brian D. Gerardot
- SUPA, Institute
of Photonics and Quantum Sciences, Heriot-Watt
University, Edinburgh EH14 4AS, United Kingdom
| | - Mauro Brotons-Gisbert
- SUPA, Institute
of Photonics and Quantum Sciences, Heriot-Watt
University, Edinburgh EH14 4AS, United Kingdom
| | - Zurab Guguchia
- Laboratory
for Muon Spin Spectroscopy, Paul Scherrer
Institute, CH-5232 Villigen PSI, Switzerland
| | - Xavier Roy
- Department
of Chemistry, Columbia University, New York, New York 10027, United States
| | - Sefaattin Tongay
- Materials
Science and Engineering, School for Engineering of Matter, Transport
and Energy, Arizona State University, Tempe, Arizona 85287, United States
| | - Ziwei Wang
- Department
of Physics and Astronomy, University of
Manchester, Manchester, M13 9PL, United Kingdom
- National
Graphene Institute, University of Manchester, Manchester, M13 9PL, United Kingdom
| | - M. Zahid Hasan
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Princeton
Institute for Science and Technology of Materials, Princeton University, Princeton, New Jersey 08544, United States
- National
High Magnetic Field Laboratory, Florida
State University, Tallahassee, Florida 32310, United States
| | - Joerg Wrachtrup
- Physikalisches
Institut, University of Stuttgart, 70569 Stuttgart, Germany
- Max Planck
Institute for Solid State Research, 70569 Stuttgart, Germany
| | - Amir Yacoby
- Department
of Physics, Harvard University, Cambridge, Massachusetts 02138, United States
- John A.
Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Albert Fert
- Donostia
International Physics Center (DIPC), 20018 Donostia-San Sebastián, Basque Country, Spain
- Unité
Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767 Palaiseau, France
- Department
of Materials Physics UPV/EHU, 20018 Donostia - San Sebastián, Basque Country, Spain
| | - Stuart Parkin
- NISE
Department, Max Planck Institute of Microstructure
Physics, 06120 Halle, Germany
| | - Kostya S. Novoselov
- Institute
for Functional Intelligent Materials, National
University of Singapore, 117544 Singapore
| | - Pengcheng Dai
- Department
of Physics and Astronomy, Rice University, Houston, Texas 77005, United States
| | - Luis Balicas
- National
High Magnetic Field Laboratory, Florida
State University, Tallahassee, Florida 32310, United States
- Department
of Physics, Florida State University, Tallahassee, Florida 32306, United States
| | - 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
- Donostia
International Physics Center (DIPC), 20018 Donostia-San Sebastián, Basque Country, Spain
- Higgs Centre
for Theoretical Physics, The University
of Edinburgh, Edinburgh EH9 3FD, United Kingdom
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19
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Stepanova M, Masell J, Lysne E, Schoenherr P, Köhler L, Paulsen M, Qaiumzadeh A, Kanazawa N, Rosch A, Tokura Y, Brataas A, Garst M, Meier D. Detection of Topological Spin Textures via Nonlinear Magnetic Responses. NANO LETTERS 2022; 22:14-21. [PMID: 34935368 PMCID: PMC8759079 DOI: 10.1021/acs.nanolett.1c02723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 11/29/2021] [Indexed: 06/14/2023]
Abstract
Topologically nontrivial spin textures, such as skyrmions and dislocations, display emergent electrodynamics and can be moved by spin currents over macroscopic distances. These unique properties and their nanoscale size make them excellent candidates for the development of next-generation race-track memory and unconventional computing. A major challenge for these applications and the investigation of nanoscale magnetic structures in general is the realization of suitable detection schemes. We study magnetic disclinations, dislocations, and domain walls in FeGe and reveal pronounced responses that distinguish them from the helimagnetic background. A combination of magnetic force microscopy (MFM) and micromagnetic simulations links the response to the local magnetic susceptibility, that is, characteristic changes in the spin texture driven by the MFM tip. On the basis of the findings, which we explain using nonlinear response theory, we propose a read-out scheme using superconducting microcoils, presenting an innovative approach for detecting topological spin textures and domain walls in device-relevant geometries.
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Affiliation(s)
- Mariia Stepanova
- Department
of Materials Science and Engineering, Norwegian
University of Science and Technology (NTNU), Trondheim 7491, Norway
- Center
for Quantum Spintronics, Department of Physics,
Norwegian University of Science and Technology (NTNU), Trondheim 7491, Norway
| | - Jan Masell
- RIKEN
Center for Emergent Matter Science (CEMS), Wako 351-0198, Japan
| | - Erik Lysne
- Department
of Materials Science and Engineering, Norwegian
University of Science and Technology (NTNU), Trondheim 7491, Norway
- Center
for Quantum Spintronics, Department of Physics,
Norwegian University of Science and Technology (NTNU), Trondheim 7491, Norway
| | - Peggy Schoenherr
- School
of Materials Science and Engineering, University
of New South Wales, Sydney, Sydney New South Wales 2052, Australia
- ARC
Centre of Excellence in Future Low-Energy Electronics Technologies
(FLEET), UNSW Sydney, Sydney, NSW 2052, Australia
| | - Laura Köhler
- Institute
of Theoretical Solid State Physics, Karlsruhe
Institute of Technology, 76049 Karlsruhe, Germany
| | - Michael Paulsen
- Physikalisch-Technische
Bundesanstalt (PTB), Berlin 10587, Germany
| | - Alireza Qaiumzadeh
- Center
for Quantum Spintronics, Department of Physics,
Norwegian University of Science and Technology (NTNU), Trondheim 7491, Norway
| | - Naoya Kanazawa
- Department
of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan
| | - Achim Rosch
- Institute
for Theoretical Physics, University of Cologne, Cologne 50937, Germany
| | - Yoshinori Tokura
- RIKEN
Center for Emergent Matter Science (CEMS), Wako 351-0198, Japan
- Department
of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan
- Tokyo
College, University of Tokyo, Tokyo 113−8656, Japan
| | - Arne Brataas
- Center
for Quantum Spintronics, Department of Physics,
Norwegian University of Science and Technology (NTNU), Trondheim 7491, Norway
| | - Markus Garst
- Institute
of Theoretical Solid State Physics, Karlsruhe
Institute of Technology, 76049 Karlsruhe, Germany
- Institute
for Quantum Materials and Technology, Karlsruhe
Institute of Technology, 76021 Karlsruhe, Germany
| | - Dennis Meier
- Department
of Materials Science and Engineering, Norwegian
University of Science and Technology (NTNU), Trondheim 7491, Norway
- Center
for Quantum Spintronics, Department of Physics,
Norwegian University of Science and Technology (NTNU), Trondheim 7491, Norway
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20
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Zang Z, Zhu Y, Xi M, Tian S, Wang T, Gu P, Peng Y, Yang S, Xu X, Li Y, Han B, Liu L, Wang Y, Gao P, Yang J, Lei H, Huang Y, Ye Y. Layer-Number-Dependent Antiferromagnetic and Ferromagnetic Behavior in MnSb_{2}Te_{4}. PHYSICAL REVIEW LETTERS 2022; 128:017201. [PMID: 35061452 DOI: 10.1103/physrevlett.128.017201] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 10/25/2021] [Accepted: 11/29/2021] [Indexed: 05/23/2023]
Abstract
MnBi_{2}Te_{4}, an intrinsic magnetic topological insulator, has shown layer-number-correlated magnetic and topological phases. More interestingly, in the isostructural material MnSb_{2}Te_{4}, the antiferromagnetic (AFM) and ferromagnetic (FM) states have been both observed in the bulk counterparts, which are also predicted to be topologically nontrivial. Revealing the layer-number-dependent magnetic properties of MnSb_{2}Te_{4} down to a single septuple layer (SL) is of great significance for exploring the topological phenomena. However, this is still elusive. Here, using the polar reflective magnetic circular dichroism spectroscopy, both the A-type AFM and FM behaviors are observed and comprehensively studied in MnSb_{2}Te_{4} down to a single SL limit. In A-type AFM MnSb_{2}Te_{4} flakes, an obvious odd-even layer-number effect is observed. An additional surface spin-flop (SSF) transition occurs in even-SL flakes with the number of layers larger than 2. With the AFM linear-chain model, we identify that the even-SL flakes stabilize in a collinear state between the SSF transition and the spin-flop transition due to their appropriate energy ratio between the magnetic-field-scale anisotropy and interlayer interaction. In FM MnSb_{2}Te_{4} flakes, we observe very different magnetic behaviors with an abrupt spin-flipping transition and very small saturation fields, indicating a weakened interlayer interaction. By revealing the rich magnetic states of few-SL MnSb_{2}Te_{4} on the parameter space of the number of layers, external magnetic field, and temperature, our findings pave the way for further quantum transport studies of few-SL MnSb_{2}Te_{4}.
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Affiliation(s)
- Zhihao Zang
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
| | - Yaozheng Zhu
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
| | - Ming Xi
- Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices, Renmin University of China, Beijing 100872, China
| | - Shangjie Tian
- Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices, Renmin University of China, Beijing 100872, China
| | - Tingting Wang
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
| | - Pingfan Gu
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
| | - Yuxuan Peng
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
| | - Shiqi Yang
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Xiaolong Xu
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
| | - Yanping Li
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
| | - Bo Han
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China
| | - Liwei Liu
- Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing 100081, China
| | - Yeliang Wang
- Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing 100081, China
| | - Peng Gao
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China
| | - Jinbo Yang
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
| | - Hechang Lei
- Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices, Renmin University of China, Beijing 100872, China
| | - Yuan Huang
- Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing 100081, China
| | - Yu Ye
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
- Beijing Key Laboratory for Magnetoelectric Materials and Devices, Beijing 100871, China
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21
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Takeuchi Y, Yamane Y, Yoon JY, Itoh R, Jinnai B, Kanai S, Ieda J, Fukami S, Ohno H. Chiral-spin rotation of non-collinear antiferromagnet by spin-orbit torque. NATURE MATERIALS 2021; 20:1364-1370. [PMID: 33986515 DOI: 10.1038/s41563-021-01005-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 04/07/2021] [Indexed: 06/12/2023]
Abstract
Electrical manipulation of magnetic materials by current-induced spin torque constitutes the basis of spintronics. Here, we show an unconventional response to spin-orbit torque of a non-collinear antiferromagnet Mn3Sn, which has attracted attention owing to its large anomalous Hall effect despite a vanishingly small net magnetization. In epitaxial heavy-metal/Mn3Sn heterostructures, we observe a characteristic fluctuation of the Hall resistance under the application of electric current. This observation is explained by a rotation of the chiral-spin structure of Mn3Sn driven by spin-orbit torque. We find that the variation of the magnitude of anomalous Hall effect fluctuation with sample size correlates with the number of magnetic domains in the Mn3Sn layer. In addition, the dependence of the critical current on Mn3Sn layer thickness reveals that spin-orbit torque generated by small current densities, below 20 MA cm-2, effectively acts on the chiral-spin structure even in Mn3Sn layers that are thicker than 20 nm. The results provide additional pathways for electrical manipulation of magnetic materials.
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Affiliation(s)
- Yutaro Takeuchi
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Aoba-ku, Sendai, Japan.
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan.
| | - Yuta Yamane
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Aoba-ku, Sendai, Japan.
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai, Japan.
| | - Ju-Young Yoon
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Aoba-ku, Sendai, Japan
| | - Ryuichi Itoh
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Aoba-ku, Sendai, Japan
| | - Butsurin Jinnai
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan
| | - Shun Kanai
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Aoba-ku, Sendai, Japan
- Center for Spintronics Research Network, Tohoku University, Sendai, Japan
- Division for the Establishment of Frontier Sciences, Tohoku University, Sendai, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, Sendai, Japan
| | - Jun'ichi Ieda
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Aoba-ku, Sendai, Japan
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Japan
| | - Shunsuke Fukami
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Aoba-ku, Sendai, Japan.
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan.
- Center for Spintronics Research Network, Tohoku University, Sendai, Japan.
- Center for Science and Innovation in Spintronics, Tohoku University, Sendai, Japan.
- Center for Innovative Integrated Electronic Systems, Tohoku University, Sendai, Japan.
| | - Hideo Ohno
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Aoba-ku, Sendai, Japan
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan
- Center for Spintronics Research Network, Tohoku University, Sendai, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, Sendai, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, Sendai, Japan
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22
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Shao J, Liu Y, Zeng M, Li J, Wu X, Ma XM, Jin F, Lu R, Sun Y, Gu M, Wang K, Wu W, Wu L, Liu C, Liu Q, Zhao Y. Pressure-Tuned Intralayer Exchange in Superlattice-Like MnBi 2Te 4/(Bi 2Te 3) n Topological Insulators. NANO LETTERS 2021; 21:5874-5880. [PMID: 34197120 DOI: 10.1021/acs.nanolett.1c01874] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The magnetic structures of MnBi2Te4(Bi2Te3)n can be manipulated by tuning the interlayer coupling via the number of Bi2Te3 spacer layers n, while the intralayer ferromagnetic (FM) exchange coupling is considered too robust to control. By applying hydrostatic pressure up to 3.5 GPa, we discover opposite responses of magnetic properties for n = 1 and 2. MnBi4Te7 stays at A-type antiferromagnetic (AFM) phase with a decreasing Néel temperature and an increasing saturation field. In sharp contrast, MnBi6Te10 experiences a phase transition from A-type AFM to a quasi-two-dimensional FM state with a suppressed saturation field under pressure. First-principles calculations reveal the essential role of intralayer exchange coupling from lattice compression in determining these magnetic properties. Such magnetic phase transition is also observed in 20% Sb-doped MnBi6Te10 because of the in-plane lattice compression.
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Affiliation(s)
- Jifeng Shao
- Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Yuntian Liu
- Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Meng Zeng
- Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Jingyuan Li
- Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Xuefeng Wu
- Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Xiao-Ming Ma
- Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Feng Jin
- Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei 230026, China
| | - Ruie Lu
- Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Yichen Sun
- Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Mingqiang Gu
- Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Kedong Wang
- Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Wenbin Wu
- Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei 230026, China
| | - Liusuo Wu
- Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Chang Liu
- Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Qihang Liu
- Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
- Guangdong Provincial Key Laboratory for Computational Science and Material Design, Southern University of Science and Technology, Shenzhen 518055, China
- Shenzhen Key Laboratory of for Advanced Quantum Functional Materials and Devices, Southern University of Science and Technology, Shenzhen 518055, China
| | - Yue Zhao
- Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
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23
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Ovchinnikov D, Huang X, Lin Z, Fei Z, Cai J, Song T, He M, Jiang Q, Wang C, Li H, Wang Y, Wu Y, Xiao D, Chu JH, Yan J, Chang CZ, Cui YT, Xu X. Intertwined Topological and Magnetic Orders in Atomically Thin Chern Insulator MnBi 2Te 4. NANO LETTERS 2021; 21:2544-2550. [PMID: 33710884 DOI: 10.1021/acs.nanolett.0c05117] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
MnBi2Te4, a van der Waals magnet, is an emergent platform for exploring Chern insulator physics. Its layered antiferromagnetic order was predicted to enable even-odd layer number dependent topological states. Furthermore, it becomes a Chern insulator when all spins are aligned by an applied magnetic field. However, the evolution of the bulk electronic structure as the magnetic state is continuously tuned and its dependence on layer number remains unexplored. Here, employing multimodal probes, we establish one-to-one correspondence between bulk electronic structure, magnetic state, topological order, and layer thickness in atomically thin MnBi2Te4 devices. As the magnetic state is tuned through the canted magnetic phase, we observe a band crossing, i.e., the closing and reopening of the bulk band gap, corresponding to the concurrent topological phase transition in both even- and odd-layer-number devices. Our findings shed new light on the interplay between band topology and magnetic order in this newly discovered topological magnet.
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Affiliation(s)
- Dmitry Ovchinnikov
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Xiong Huang
- Department of Physics and Astronomy, University of California, Riverside, California 92521, United States
- Department of Materials Science and Engineering, University of California, Riverside, California 92521, United States
| | - Zhong Lin
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Zaiyao Fei
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Jiaqi Cai
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Tiancheng Song
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Minhao He
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Qianni Jiang
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Chong Wang
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Hao Li
- School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, People's Republic of China
| | - Yayu Wang
- Department of Physics, Tsinghua University, Beijing 100084, People's Republic of China
| | - Yang Wu
- Department of Mechanical Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Di Xiao
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Jiun-Haw Chu
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Jiaqiang Yan
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Cui-Zu Chang
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Yong-Tao Cui
- Department of Physics and Astronomy, University of California, Riverside, California 92521, United States
| | - Xiaodong Xu
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
- Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195, United States
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24
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Finco A, Haykal A, Tanos R, Fabre F, Chouaieb S, Akhtar W, Robert-Philip I, Legrand W, Ajejas F, Bouzehouane K, Reyren N, Devolder T, Adam JP, Kim JV, Cros V, Jacques V. Imaging non-collinear antiferromagnetic textures via single spin relaxometry. Nat Commun 2021; 12:767. [PMID: 33536440 PMCID: PMC7859235 DOI: 10.1038/s41467-021-20995-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 01/04/2021] [Indexed: 01/30/2023] Open
Abstract
Antiferromagnetic materials are promising platforms for next-generation spintronics owing to their fast dynamics and high robustness against parasitic magnetic fields. However, nanoscale imaging of the magnetic order in such materials with zero net magnetization remains a major experimental challenge. Here we show that non-collinear antiferromagnetic spin textures can be imaged by probing the magnetic noise they locally produce via thermal populations of magnons. To this end, we perform nanoscale, all-optical relaxometry with a scanning quantum sensor based on a single nitrogen-vacancy (NV) defect in diamond. Magnetic noise is detected through an increase of the spin relaxation rate of the NV defect, which results in an overall reduction of its photoluminescence signal under continuous laser illumination. As a proof-of-concept, the efficiency of the method is demonstrated by imaging various spin textures in synthetic antiferromagnets, including domain walls, spin spirals and antiferromagnetic skyrmions. This imaging procedure could be extended to a large class of intrinsic antiferromagnets and opens up new opportunities for studying the physics of localized spin wave modes for magnonics.
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Affiliation(s)
- Aurore Finco
- Laboratoire Charles Coulomb, Université de Montpellier and CNRS, 34095, Montpellier, France
| | - Angela Haykal
- Laboratoire Charles Coulomb, Université de Montpellier and CNRS, 34095, Montpellier, France
| | - Rana Tanos
- Laboratoire Charles Coulomb, Université de Montpellier and CNRS, 34095, Montpellier, France
| | - Florentin Fabre
- Laboratoire Charles Coulomb, Université de Montpellier and CNRS, 34095, Montpellier, France
| | - Saddem Chouaieb
- Laboratoire Charles Coulomb, Université de Montpellier and CNRS, 34095, Montpellier, France
| | - Waseem Akhtar
- Laboratoire Charles Coulomb, Université de Montpellier and CNRS, 34095, Montpellier, France
- Department of Physics, JMI, Central University, New Delhi, India
| | - Isabelle Robert-Philip
- Laboratoire Charles Coulomb, Université de Montpellier and CNRS, 34095, Montpellier, France
| | - William Legrand
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767, Palaiseau, France
| | - Fernando Ajejas
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767, Palaiseau, France
| | - Karim Bouzehouane
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767, Palaiseau, France
| | - Nicolas Reyren
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767, Palaiseau, France
| | - Thibaut Devolder
- Centre de Nanosciences et de Nanotechnologies, CNRS, Université Paris-Saclay, 91120, Palaiseau, France
| | - Jean-Paul Adam
- Centre de Nanosciences et de Nanotechnologies, CNRS, Université Paris-Saclay, 91120, Palaiseau, France
| | - Joo-Von Kim
- Centre de Nanosciences et de Nanotechnologies, CNRS, Université Paris-Saclay, 91120, Palaiseau, France
| | - Vincent Cros
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767, Palaiseau, France
| | - Vincent Jacques
- Laboratoire Charles Coulomb, Université de Montpellier and CNRS, 34095, Montpellier, France.
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Sass PM, Kim J, Vanderbilt D, Yan J, Wu W. Robust A-Type Order and Spin-Flop Transition on the Surface of the Antiferromagnetic Topological Insulator MnBi_{2}Te_{4}. PHYSICAL REVIEW LETTERS 2020; 125:037201. [PMID: 32745385 DOI: 10.1103/physrevlett.125.037201] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Accepted: 06/12/2020] [Indexed: 06/11/2023]
Abstract
Here, we present microscopic evidence of the persistence of uniaxial A-type antiferromagnetic order to the surface layers of MnBi_{2}Te_{4} single crystals using magnetic force microscopy. Our results reveal termination-dependent magnetic contrast across both surface step edges and domain walls, which can be screened by thin layers of soft magnetism. The robust surface A-type order is further corroborated by the observation of termination-dependent surface spin-flop transitions, which have been theoretically proposed decades ago. Our results not only provide key ingredients for understanding the electronic properties of the antiferromagnetic topological insulator MnBi_{2}Te_{4}, but also open a new paradigm for exploring intrinsic surface metamagnetic transitions in natural antiferromagnets.
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Affiliation(s)
- Paul M Sass
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Jinwoong Kim
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Jiaqiang Yan
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Weida Wu
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
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