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Ye L, Sorensen ME, Bachmann MD, Fisher IR. Measurement of the magnetic octupole susceptibility of PrV 2Al 20. Nat Commun 2024; 15:7005. [PMID: 39143053 PMCID: PMC11325040 DOI: 10.1038/s41467-024-51269-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 08/02/2024] [Indexed: 08/16/2024] Open
Abstract
Revealing the presence of magnetic octupole order and associated octupole fluctuations in solids is a highly challenging task due to the lack of simple external fields that can couple to magnetic octupoles. Here, we demonstrate a methodology for probing the magnetic octupole susceptibility of a candidate material, PrV2Al20, using a product of magnetic field Hi and shear strain ϵjk as a composite effective field, while employing an adiabatic elastocaloric effect to probe the response. We observe Curie-Weiss behavior in the obtained octupolar susceptibility down to approximately 3 K. Although octupole order does not appear to be the leading multipolar channel in PrV2Al20, our results nevertheless reveal the presence of strong magnetic octupole fluctuations and hence demonstrate that octupole order is at least a competing state. More broadly, our results highlight how anisotropic strain can be combined with magnetic fields to probe elusive 'hidden' electronic orders.
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Affiliation(s)
- Linda Ye
- Department of Applied Physics, Stanford University, Stanford, CA, USA.
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA, USA.
- Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA, USA.
| | - Matthew E Sorensen
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA, USA
- Department of Physics, Stanford University, Stanford, CA, USA
| | - Maja D Bachmann
- Department of Applied Physics, Stanford University, Stanford, CA, USA
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA, USA
| | - Ian R Fisher
- Department of Applied Physics, Stanford University, Stanford, CA, USA.
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA, USA.
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2
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Chen Y, Samanta K, Shahed NA, Zhang H, Fang C, Ernst A, Tsymbal EY, Parkin SSP. Twist-assisted all-antiferromagnetic tunnel junction in the atomic limit. Nature 2024:10.1038/s41586-024-07818-x. [PMID: 39143222 DOI: 10.1038/s41586-024-07818-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Accepted: 07/11/2024] [Indexed: 08/16/2024]
Abstract
Antiferromagnetic spintronics1,2 shows great potential for high-density and ultrafast information devices. Magnetic tunnel junctions (MTJs), a key spintronic memory component that are typically formed from ferromagnetic materials, have seen rapid developments very recently using antiferromagnetic materials3,4. Here we demonstrate a twisting strategy for constructing all-antiferromagnetic tunnel junctions down to the atomic limit. By twisting two bilayers of CrSBr, a 2D antiferromagnet (AFM), a more than 700% nonvolatile tunnelling magnetoresistance (TMR) ratio is shown at zero field (ZF) with the entire twisted stack acting as the tunnel barrier. This is determined by twisting two CrSBr monolayers for which the TMR is shown to be derived from accumulative coherent tunnelling across the individual CrSBr monolayers. The dependence of the TMR on the twist angle is calculated from the electron-parallel momentum-dependent decay across the twisted monolayers. This is in excellent agreement with our experiments that consider twist angles that vary from 0° to 90°. Moreover, we also find that the temperature dependence of the TMR is, surprisingly, much weaker for the twisted as compared with the untwisted junctions, making the twisted junctions even more attractive for applications. Our work shows that it is possible to push nonvolatile magnetic information storage to the atomically thin limit.
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Affiliation(s)
- Yuliang Chen
- Max Planck Institute of Microstructure Physics, Halle, Germany
| | - Kartik Samanta
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, NE, USA
- Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Naafis A Shahed
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, NE, USA
- Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Haojie Zhang
- Max Planck Institute of Microstructure Physics, Halle, Germany
| | - Chi Fang
- Max Planck Institute of Microstructure Physics, Halle, Germany
| | - Arthur Ernst
- Max Planck Institute of Microstructure Physics, Halle, Germany
- Institute of Theoretical Physics, Johannes Kepler University, Linz, Austria
| | - Evgeny Y Tsymbal
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, NE, USA
- Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, NE, USA
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3
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Asakura M, Higo T, Matsuo T, Uesugi R, Nishio-Hamane D, Nakatsuji S. Observation of Omnidirectional Exchange Bias at All-Antiferromagnetic Polycrystalline Heterointerface. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2400301. [PMID: 38531113 DOI: 10.1002/adma.202400301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Revised: 03/13/2024] [Indexed: 03/28/2024]
Abstract
Due to promising functionalities that may dramatically enhance spintronics performance, antiferromagnets are the subject of intensive research for developing the next-generation active elements to replace ferromagnets. In particular, the recent experimental demonstration of tunneling magnetoresistance and electrical switching using chiral antiferromagnets has sparked expectations for the practical integration of antiferromagnetic materials into device architectures. To further develop the technology to manipulate the magnetic anisotropies in all-antiferromagnetic devices, it is essential to realize exchange bias through the interface between antiferromagnetic multilayers. Here, the first observation on the omnidirectional exchange bias at an all-antiferromagnetic polycrystalline heterointerface is reported. This experiment demonstrates that the interfacial energy causing the exchange bias between the chiral-antiferromagnet Mn3Sn/collinear-antiferromagnet MnN layers is comparable to those found at the conventional ferromagnet/antiferromagnet interface at room temperature. In sharp contrast with previous reports using ferromagnets, the magnetic field control of the unidirectional anisotropy is found to be omnidirectional due to the absence of the shape anisotropy in the antiferromagnetic multilayer. The realization of the omnidirectional exchange bias at the interface between polycrystalline antiferromagnets on amorphous templates, highly compatible with existing Si-based devices, paves the way for developing ultra-low power and ultra-high speed memory devices based on antiferromagnets.
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Affiliation(s)
- Mihiro Asakura
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Tomoya Higo
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
- CREST, Japan Science and Technology Agency, Kawaguchi, Saitama, 332-0012, Japan
| | - Takumi Matsuo
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
- Institute for Quantum Matter and Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Ryota Uesugi
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - Daisuke Nishio-Hamane
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - Satoru Nakatsuji
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
- CREST, Japan Science and Technology Agency, Kawaguchi, Saitama, 332-0012, Japan
- Institute for Quantum Matter and Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD, 21218, USA
- Trans-scale Quantum Science Institute, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
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4
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Johnson F, Rendell-Bhatti F, Esser BD, Hussey A, McComb DW, Zemen J, Boldrin D, Cohen LF. The Impact of Local Strain Fields in Noncollinear Antiferromagnetic Films. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2401180. [PMID: 38618946 DOI: 10.1002/adma.202401180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 03/20/2024] [Indexed: 04/16/2024]
Abstract
Antiferromagnets hosting structural or magnetic order that breaks time reversal symmetry are of increasing interest for "beyond von Neumann" computing applications because the topology of their band structure allows for intrinsic physical properties, exploitable in integrated memory and logic function. One such group are the noncollinear antiferromagnets. Essential for domain manipulation is the existence of small net moments found routinely when the material is synthesized in thin film form and attributed to symmetry breaking caused by spin canting, either from the Dzyaloshinskii-Moriya interaction or from strain. Although the spin arrangement of these materials makes them highly sensitive to strain, there is little understanding about the influence of local strain fields caused by lattice defects on global properties, such as magnetization and anomalous Hall effect. This premise is investigated by examining noncollinear antiferromagnetic films that are either highly lattice mismatched or closely matched to their substrate. In either case, edge dislocation networks are generated and for the former case, these extend throughout the entire film thickness, creating large local strain fields. These strain fields allow for finite intrinsic magnetization in seemingly structurally relaxed films and influence the antiferromagnetic domain state and the intrinsic anomalous Hall effect.
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Affiliation(s)
- Freya Johnson
- Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK
| | | | - Bryan D Esser
- Monash Centre for Electron Microscopy, Monash University, Melbourne, 3800, Australia
| | - Aisling Hussey
- School of Physics, CRANN and AMBER, Trinity College Dublin, Dublin, D02PN40, Ireland
| | - David W McComb
- Center for Electron Microscopy and Analysis, The Ohio State University, Columbus, OH, 43212, USA
| | - Jan Zemen
- Faculty of Electrical Engineering, Czech Technical University in Prague, Technická 2, Prague, 160 00 Praha 6, Czech Republic
| | - David Boldrin
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Lesley F Cohen
- Department of Physics, Blackett Laboratory, Imperial College London, London, SW7 2AZ, UK
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5
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Wu M, Chen T, Nomoto T, Tserkovnyak Y, Isshiki H, Nakatani Y, Higo T, Tomita T, Kondou K, Arita R, Nakatsuji S, Otani Y. Current-driven fast magnetic octupole domain-wall motion in noncollinear antiferromagnets. Nat Commun 2024; 15:4305. [PMID: 38862480 PMCID: PMC11166987 DOI: 10.1038/s41467-024-48440-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Accepted: 05/01/2024] [Indexed: 06/13/2024] Open
Abstract
Antiferromagnets (AFMs) have the natural advantages of terahertz spin dynamics and negligible stray fields, thus appealing for use in domain-wall applications. However, their insensitive magneto-electric responses make controlling them in domain-wall devices challenging. Recent research on noncollinear chiral AFMs Mn3X (X = Sn, Ge) enabled us to detect and manipulate their magnetic octupole domain states. Here, we demonstrate a current-driven fast magnetic octupole domain-wall (MODW) motion in Mn3X. The magneto-optical Kerr observation reveals the Néel-like MODW of Mn3Ge can be accelerated up to 750 m s-1 with a current density of only 7.56 × 1010 A m-2 without external magnetic fields. The MODWs show extremely high mobility with a small critical current density. We theoretically extend the spin-torque phenomenology for domain-wall dynamics from collinear to noncollinear magnetic systems. Our study opens a new route for antiferromagnetic domain-wall-based applications.
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Affiliation(s)
- Mingxing Wu
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
- Center for Emergent Matter Science, RIKEN, 2-1 Hirosawa, Wako, 351-0198, Japan
| | - Taishi Chen
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
- Key Laboratory of Quantum Materials and Devices of Ministry of Education, School of Physics, Southeast University, Nanjing, 211189, China
- Department of Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Takuya Nomoto
- Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1 Meguro-ku, Tokyo, 153-8904, Japan
| | - Yaroslav Tserkovnyak
- Department of Physics and Astronomy and Bhaumik Institute for Theoretical Physics, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Hironari Isshiki
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
- CREST, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan
| | - Yoshinobu Nakatani
- Department of Computer Science, University of Electro-Communications, 1-5-1 Chofugaoka, Chofu-Shi, Tokyo, 182-8585, Japan
| | - Tomoya Higo
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
- Department of Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
- CREST, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan
| | - Takahiro Tomita
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
- Department of Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
- CREST, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan
| | - Kouta Kondou
- Center for Emergent Matter Science, RIKEN, 2-1 Hirosawa, Wako, 351-0198, Japan
- CREST, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan
| | - Ryotaro Arita
- Center for Emergent Matter Science, RIKEN, 2-1 Hirosawa, Wako, 351-0198, Japan
- Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1 Meguro-ku, Tokyo, 153-8904, Japan
- CREST, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan
| | - Satoru Nakatsuji
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
- Department of Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
- CREST, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan
- Trans-Scale Quantum Science Institute, University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Yoshichika Otani
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan.
- Center for Emergent Matter Science, RIKEN, 2-1 Hirosawa, Wako, 351-0198, Japan.
- CREST, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan.
- Trans-Scale Quantum Science Institute, University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
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6
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Zhou C, Zhou J. Light-Induced Topological Phase Transition with Tunable Layer Hall Effect in Axion Antiferromagnets. NANO LETTERS 2024. [PMID: 38848333 DOI: 10.1021/acs.nanolett.4c01415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2024]
Abstract
The intricate interplay between light and matter provides effective tools for manipulating topological phenomena. Here, we theoretically propose and computationally show that circularly polarized light holds the potential to transform the axion insulating phase into a quantum anomalous Hall state in MnBi2Te4 thin films, featuring tunable Chern numbers (ranging up to ±2). In particular, we reveal the spatial rearrangement of the hidden layer-resolved anomalous Hall effect under light-driven Floquet engineering. Notably, upon Bi2Te3 layer intercalation, the anomalous Hall conductance predominantly localizes in the nonmagnetic Bi2Te3 layers that hold zero Berry curvature in the intact state, suggesting a significant magnetic proximity effect. Additionally, we estimate variations in the magneto-optical Kerr effect, giving a contactless method for detecting topological transitions. Our work not only presents a strategy to investigate emergent topological phases but also sheds light on the possible applications of the layer Hall effect in topological antiferromagnetic spintronics.
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Affiliation(s)
- Cong Zhou
- Center for Alloy Innovation and Design, State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Jian Zhou
- Center for Alloy Innovation and Design, State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, 710049, China
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7
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Isshiki H, Budai N, Kobayashi A, Uesugi R, Higo T, Nakatsuji S, Otani Y. Observation of Cluster Magnetic Octupole Domains in the Antiferromagnetic Weyl Semimetal Mn_{3}Sn Nanowire. PHYSICAL REVIEW LETTERS 2024; 132:216702. [PMID: 38856290 DOI: 10.1103/physrevlett.132.216702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Accepted: 04/19/2024] [Indexed: 06/11/2024]
Abstract
The antiferromagnetic Weyl semimetal Mn_{3}Sn has attracted wide attention due to its vast anomalous transverse transport properties despite barely any net magnetization. So far, the magnetic properties of Mn_{3}Sn have been experimentally investigated on micrometer scale samples but not in nanometers. In this study, we measured the local anomalous Nernst effect of a (0001)-textured Mn_{3}Sn nanowire using a tip-contact-induced temperature gradient with an atomic force microscope. Our approach directly maps the distribution of the cluster magnetic octupole moments with 80 nm spatial resolution, providing crucial information for integrating the Mn_{3}Sn nanostructure into spintronic devices.
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Affiliation(s)
- Hironari Isshiki
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
- CREST, Japan Science and Technology Agency (JST), Saitama 332-0012, Japan
| | - Nico Budai
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Ayuko Kobayashi
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Ryota Uesugi
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Tomoya Higo
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
- CREST, Japan Science and Technology Agency (JST), Saitama 332-0012, Japan
- Department of Physics, The University of Tokyo; Bunkyo-ku, Tokyo 113-0033, Japan
| | - Satoru Nakatsuji
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
- CREST, Japan Science and Technology Agency (JST), Saitama 332-0012, Japan
- Department of Physics, The University of Tokyo; Bunkyo-ku, Tokyo 113-0033, Japan
- Trans-scale Quantum Science Institute, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - YoshiChika Otani
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
- CREST, Japan Science and Technology Agency (JST), Saitama 332-0012, Japan
- Trans-scale Quantum Science Institute, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
- Center for Emergent Matter Science RIKEN, Wako, Saitama 51-0198, Japan
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8
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Feng J, Zhou X, Xu M, Shi J, Li Y. Layer Control of Magneto-Optical Effects and Their Quantization in Spin-Valley Splitting Antiferromagnets. NANO LETTERS 2024; 24:3898-3905. [PMID: 38525906 DOI: 10.1021/acs.nanolett.3c05052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
Abstract
Magneto-optical effects (MOE), interfacing the fundamental interplay between magnetism and light, have served as a powerful probe for magnetic order, band topology, and valley index. Here, based on multiferroic and topological bilayer antiferromagnets (AFMs), we propose a layer control of MOE (L-MOE), which is created and annihilated by layer-stacking or an electric field effect. The key character of L-MOE is the sign-reversible response controlled by ferroelectric polarization, the Néel vector, or the electric field direction. Moreover, the sign-reversible L-MOE can be quantized in topologically insulating AFMs. We reveal that the switchable L-MOE originates from the combined contributions of spin-conserving and spin-flip interband transitions in spin-valley splitting AFMs, a phenomenon not observed in conventional AFMs. Our findings bridge the ancient MOE to the emergent realms of layertronics, valleytronics, and multiferroics and may hold immense potential in these fields.
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Affiliation(s)
- Jiaqi Feng
- Laboratory of Quantum Functional Materials Design and Application, School of Physics and Electronic Engineering, Jiangsu Normal University, Xuzhou 221116, China
| | - Xiaodong Zhou
- Laboratory of Quantum Functional Materials Design and Application, School of Physics and Electronic Engineering, Jiangsu Normal University, Xuzhou 221116, China
| | - Meiling Xu
- Laboratory of Quantum Functional Materials Design and Application, School of Physics and Electronic Engineering, Jiangsu Normal University, Xuzhou 221116, China
| | - Jingming Shi
- Laboratory of Quantum Functional Materials Design and Application, School of Physics and Electronic Engineering, Jiangsu Normal University, Xuzhou 221116, China
| | - Yinwei Li
- Laboratory of Quantum Functional Materials Design and Application, School of Physics and Electronic Engineering, Jiangsu Normal University, Xuzhou 221116, China
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9
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Chen H, Liu L, Zhou X, Meng Z, Wang X, Duan Z, Zhao G, Yan H, Qin P, Liu Z. Emerging Antiferromagnets for Spintronics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2310379. [PMID: 38183310 DOI: 10.1002/adma.202310379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Revised: 12/18/2023] [Indexed: 01/08/2024]
Abstract
Antiferromagnets constitute promising contender materials for next-generation spintronic devices with superior stability, scalability, and dynamics. Nevertheless, the perception of well-established ferromagnetic spintronics underpinned by spontaneous magnetization seemed to indicate the inadequacy of antiferromagnets for spintronics-their compensated magnetization has been perceived to result in uncontrollable antiferromagnetic order and subtle magnetoelectronic responses. However, remarkable advancements have been achieved in antiferromagnetic spintronics in recent years, with consecutive unanticipated discoveries substantiating the feasibility of antiferromagnet-centered spintronic devices. It is emphasized that, distinct from ferromagnets, the richness in complex antiferromagnetic crystal structures is the unique and essential virtue of antiferromagnets that can open up their endless possibilities of novel phenomena and functionality for spintronics. In this Perspective, the recent progress in antiferromagnetic spintronics is reviewed, with a particular focus on that based on several kinds of antiferromagnets with special antiferromagnetic crystal structures. The latest developments in efficiently manipulating antiferromagnetic order, exploring novel antiferromagnetic physical responses, and demonstrating prototype antiferromagnetic spintronic devices are discussed. An outlook on future research directions is also provided. It is hoped that this Perspective can serve as guidance for readers who are interested in this field and encourage unprecedented studies on antiferromagnetic spintronic materials, phenomena, and devices.
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Affiliation(s)
- Hongyu Chen
- School of Materials Science and Engineering, Beihang University, Beijing, 100191, China
| | - Li Liu
- School of Materials Science and Engineering, Beihang University, Beijing, 100191, China
| | - Xiaorong Zhou
- School of Materials Science and Engineering, Beihang University, Beijing, 100191, China
| | - Ziang Meng
- School of Materials Science and Engineering, Beihang University, Beijing, 100191, China
| | - Xiaoning Wang
- School of Materials Science and Engineering, Beihang University, Beijing, 100191, China
| | - Zhiyuan Duan
- School of Materials Science and Engineering, Beihang University, Beijing, 100191, China
| | - Guojian Zhao
- School of Materials Science and Engineering, Beihang University, Beijing, 100191, China
| | - Han Yan
- School of Materials Science and Engineering, Beihang University, Beijing, 100191, China
| | - Peixin Qin
- School of Materials Science and Engineering, Beihang University, Beijing, 100191, China
| | - Zhiqi Liu
- School of Materials Science and Engineering, Beihang University, Beijing, 100191, China
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10
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Zhang W, Fu S, Man Z. Magneto-optical-like effect in tight focusing of azimuthally polarized sine-Gaussian beams. OPTICS EXPRESS 2024; 32:11363-11376. [PMID: 38570985 DOI: 10.1364/oe.521000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 03/04/2024] [Indexed: 04/05/2024]
Abstract
Magneto-optical effects, which have been known for over a century, are among the most fundamental phenomena in physics and describe changes in the polarization state of light when it interacts with magnetic materials. When a polarized plane wave propagates in or through a homogeneous and isotropic transparent medium, it is generally accepted that its transverse polarization structure remains unchanged. However, we show that a strong radial polarization component can be generated when an azimuthally polarized sine-Gaussian plane wave is tightly focused by a high numerical aperture lens, resulting in a magneto-optical-like effect that does not require external magnetic field or magnetic medium. Calculations show that the intensity structure and polarization distribution of the highly confined electric field strongly depend on the parameters m and φ0 in the sinusoidal term, where m can be used to control the number of the multifocal spots and φ0 can be used to control the position of each focal spot. Finally, we show that this peculiar electric field distribution can be used to realize multiple particles trapping with controllable numbers and locations.
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11
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Wang R, Zhang J, Li T, Chen K, Li Z, Wu M, Ling L, Xi C, Hong K, Miao L, Yuan S, Chen T, Wang J. SdH Oscillations from the Dirac Surface State in the Fermi-Arc Antiferromagnet NdBi. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2303978. [PMID: 37877606 PMCID: PMC10724392 DOI: 10.1002/advs.202303978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 08/31/2023] [Indexed: 10/26/2023]
Abstract
The recent progress in CuMnAs and Mn3X (X = Sn, Ge, Pt) shows that antiferromagnets (AFMs) provide a promising platform for advanced spintronics device innovations. Most recently, a switchable Fermi-arc is discovered by the ARPES technique in antiferromagnet NdBi, but the knowledge about electron-transport property and the manipulability of the magnetic structure in NdBi is still vacant to date. In this study, SdH oscillations are successfully verified from the Dirac surface states (SSs) with 2-dimensionality and nonzero Berry phase. Particularly, it is observed that the spin-flop transition only appears when the external magnetical field is applied along [001] direction, and features obvious hysteresis for the first time in NdBi, which provides a powerful handle for adjusting the spin texture in NdBi. Crucially, the DFT shows the Dirac cone and the Fermi arc strongly depend on the high-order magnetic structure of NdBi and further reveals the orbital magnetic moment of Nd plays a crucial role in fostering the peculiar SSs, leading to unveil the mystery of the band-splitting effect and to manipulate the electronic transport, high-effectively, in the thin film works in NdBi. It is believed that this study provides important guidance for the development of new antiferromagnet-based spintronics devices based on cutting-edge rare-earth monopnictides.
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Affiliation(s)
- Ruoqi Wang
- Key Laboratory of Quantum Materials and Devices of Ministry of EducationSchool of PhysicsSoutheast UniversityNanjing211189China
| | - Junchao Zhang
- Key Laboratory of Quantum Materials and Devices of Ministry of EducationSchool of PhysicsSoutheast UniversityNanjing211189China
| | - Tian Li
- High Magnetic Field LaboratoryChinese Academy of SciencesHefei230031China
| | - Keming Chen
- Key Laboratory of Quantum Materials and Devices of Ministry of EducationSchool of PhysicsSoutheast UniversityNanjing211189China
| | - Zhengyu Li
- High Magnetic Field LaboratoryChinese Academy of SciencesHefei230031China
| | - Mingliang Wu
- Key Laboratory of Quantum Materials and Devices of Ministry of EducationSchool of PhysicsSoutheast UniversityNanjing211189China
| | - Langsheng Ling
- High Magnetic Field LaboratoryChinese Academy of SciencesHefei230031China
| | - Chuanying Xi
- High Magnetic Field LaboratoryChinese Academy of SciencesHefei230031China
| | - Kunquan Hong
- Key Laboratory of Quantum Materials and Devices of Ministry of EducationSchool of PhysicsSoutheast UniversityNanjing211189China
| | - Lin Miao
- Key Laboratory of Quantum Materials and Devices of Ministry of EducationSchool of PhysicsSoutheast UniversityNanjing211189China
| | - Shijun Yuan
- Key Laboratory of Quantum Materials and Devices of Ministry of EducationSchool of PhysicsSoutheast UniversityNanjing211189China
| | - Taishi Chen
- Key Laboratory of Quantum Materials and Devices of Ministry of EducationSchool of PhysicsSoutheast UniversityNanjing211189China
| | - Jinlan Wang
- Key Laboratory of Quantum Materials and Devices of Ministry of EducationSchool of PhysicsSoutheast UniversityNanjing211189China
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12
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Xie H, Zhang N, Ma Y, Chen X, Ke L, Wu Y. Efficient Noncollinear Antiferromagnetic State Switching Induced by the Orbital Hall Effect in Chromium. NANO LETTERS 2023; 23:10274-10281. [PMID: 37909311 DOI: 10.1021/acs.nanolett.3c02797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2023]
Abstract
Recently, orbital Hall current has attracted attention as an alternative method to switch the magnetization of ferromagnets. Here we present our findings on electrical switching of the antiferromagnetic state in Mn3Sn/Cr, where despite the much smaller spin Hall angle of Cr, the switching current density is comparable to heavy metal-based heterostructures. However, the inverse process, i.e., spin-to-charge conversion in Cr-based heterostructures, is much less efficient than the Pt-based equivalents, as manifested in the 1 order of magnitude smaller terahertz emission intensity and spin current-induced magnetoresistance. These results in combination with the slow decay of terahertz emission against Cr thickness (diffusion length of ∼11 nm) suggest that the observed magnetic switching can be attributed to orbital current generation in Cr, followed by efficient conversion to spin current. Our work demonstrates the potential of light metals like Cr as efficient orbital/spin current sources for antiferromagnetic spintronics.
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Affiliation(s)
- Hang Xie
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
| | - Nan Zhang
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research, Singapore 138634, Singapore
| | - Yuteng Ma
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
- National University of Singapore (Chong Qing) Research Institute, Chongqing Liang Jiang New Area, Chongqing 401123, China
| | - Xin Chen
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
| | - Lin Ke
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research, Singapore 138634, Singapore
| | - Yihong Wu
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
- National University of Singapore (Chong Qing) Research Institute, Chongqing Liang Jiang New Area, Chongqing 401123, China
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13
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Wang P, Liu Q, Liu N, Kuang M, Yang T, Wang B, Ju M, Yuan H, Jiang X, Zhao J. Electric Field-Controlled Magneto-Optical Kerr Effect in A-Type Antiferromagnetic Fe 2CX 2 (X = F, Cl) and Its Janus Monolayer. ACS APPLIED MATERIALS & INTERFACES 2023. [PMID: 37916432 DOI: 10.1021/acsami.3c11811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2023]
Abstract
The magneto-optical Kerr effect (MOKE) is a powerful probe of magnetism and has recently gained new attention in antiferromagnetic (AFM) materials. Through extensive first-principles calculations and group theory analysis, we have identified Fe2CX2 (X = F, Cl) and Janus Fe2CFCl monolayers as ideal A-type collinear AFM materials with high magnetic anisotropy and Néel temperatures. By applying a vertical external electrical field (Ef) of 0.2 V/Å, the MOKE is activated for Fe2CF2 and Fe2CCl2 monolayers without changing their magnetic ground state, and the maximum Kerr rotation angles are 0.13 and 0.08°, respectively. Due to the out-of-plane spontaneous polarization, the intrinsic and nonvolatile MOKE is found in the Janus Fe2CFCl monolayer and the maximal Kerr rotation angle without external electronic field is 0.25°. Moreover, the intrinsic built-in electronic field also gives origin to more robust A-type AFM ordering and reversible Kerr angle against external Ef. Our study suggests that Ef is an effective tool for controlling MOKE in two-dimensional (2D) AFM materials. This research opens the possibility of related studies and applications in AFM spintronics.
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Affiliation(s)
- Peng Wang
- Chongqing Key Laboratory of Micro & Nano Structure Optoelectronics, School of Physical Science and Technology, Southwest University, Chongqing 400715, China
| | - Qinxi Liu
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, (Dalian University of Technology), Ministry of Education, Dalian 116024, China
| | - Nanshu Liu
- Department of Physics and Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-nano Devices, Renmin University of China, Beijing 100190, China
| | - Minquan Kuang
- Chongqing Key Laboratory of Micro & Nano Structure Optoelectronics, School of Physical Science and Technology, Southwest University, Chongqing 400715, China
| | - Tie Yang
- Chongqing Key Laboratory of Micro & Nano Structure Optoelectronics, School of Physical Science and Technology, Southwest University, Chongqing 400715, China
| | - Biao Wang
- Chongqing Key Laboratory of Micro & Nano Structure Optoelectronics, School of Physical Science and Technology, Southwest University, Chongqing 400715, China
| | - Meng Ju
- Chongqing Key Laboratory of Micro & Nano Structure Optoelectronics, School of Physical Science and Technology, Southwest University, Chongqing 400715, China
| | - Hongkuan Yuan
- Chongqing Key Laboratory of Micro & Nano Structure Optoelectronics, School of Physical Science and Technology, Southwest University, Chongqing 400715, China
| | - Xue Jiang
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, (Dalian University of Technology), Ministry of Education, Dalian 116024, China
| | - Jijun Zhao
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, (Dalian University of Technology), Ministry of Education, Dalian 116024, China
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14
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Kim D, Pandey J, Jeong J, Cho W, Lee S, Cho S, Yang H. Phase Engineering of 2D Materials. Chem Rev 2023; 123:11230-11268. [PMID: 37589590 DOI: 10.1021/acs.chemrev.3c00132] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/18/2023]
Abstract
Polymorphic 2D materials allow structural and electronic phase engineering, which can be used to realize energy-efficient, cost-effective, and scalable device applications. The phase engineering covers not only conventional structural and metal-insulator transitions but also magnetic states, strongly correlated band structures, and topological phases in rich 2D materials. The methods used for the local phase engineering of 2D materials include various optical, geometrical, and chemical processes as well as traditional thermodynamic approaches. In this Review, we survey the precise manipulation of local phases and phase patterning of 2D materials, particularly with ideal and versatile phase interfaces for electronic and energy device applications. Polymorphic 2D materials and diverse quantum materials with their layered, vertical, and lateral geometries are discussed with an emphasis on the role and use of their phase interfaces. Various phase interfaces have demonstrated superior and unique performance in electronic and energy devices. The phase patterning leads to novel homo- and heterojunction structures of 2D materials with low-dimensional phase boundaries, which highlights their potential for technological breakthroughs in future electronic, quantum, and energy devices. Accordingly, we encourage researchers to investigate and exploit phase patterning in emerging 2D materials.
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Affiliation(s)
- Dohyun Kim
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Juhi Pandey
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Juyeong Jeong
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Woohyun Cho
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Seungyeon Lee
- Division of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul 03760, Korea
| | - Suyeon Cho
- Division of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul 03760, Korea
| | - Heejun Yang
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
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15
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Galluzzi A, Buchkov K, Blagoev BS, Paskaleva A, Avramova I, Mehandhziev V, Tzvetkov P, Terziyska P, Kovacheva D, Polichetti M. Strong Magneto-Optical Kerr Effects in Ni-Doped ZnO Nanolaminate Structures Obtained by Atomic Layer Deposition. MATERIALS (BASEL, SWITZERLAND) 2023; 16:6547. [PMID: 37834684 PMCID: PMC10574388 DOI: 10.3390/ma16196547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 09/26/2023] [Accepted: 09/28/2023] [Indexed: 10/15/2023]
Abstract
The magneto-optical (MO) Kerr effects for ZnO and ZnO:Ni-doped nanolaminate structures prepared using atomic layer deposition (ALD) have been investigated. The chemical composition and corresponding structural and morphological properties were studied using XRD and XPS and compared for both nanostructures. The 2D array gradient maps of microscale variations of the Kerr angle polarization rotation were acquired by means of MO Kerr microscopy. The obtained data revealed complex behavior and broad statistical dispersion and showed distinct qualitative and quantitative differences between the undoped ZnO and ZnO:Ni-doped nanolaminates. The detected magneto-optical response is extensively inhomogeneous in ZnO:Ni films, and a giant Kerr polarization rotation angle reaching up to ~2° was established. This marks the prospects for further development of magneto-optical effects in ALD ZnO modified by transition metal oxide nanostructures.
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Affiliation(s)
- Armando Galluzzi
- Department of Physics ‘E.R. Caianiello’, University of Salerno, via Giovanni Paolo II, 132, Fisciano, I-84084 Salerno, Italy; (A.G.); (M.P.)
- CNR-SPIN Salerno, via Giovanni Paolo II, 132, Fisciano, I-84084 Salerno, Italy
| | - Krastyo Buchkov
- Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee Blvd., 1784 Sofia, Bulgaria; (B.S.B.); (A.P.); (V.M.); (P.T.)
| | - Blagoy S. Blagoev
- Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee Blvd., 1784 Sofia, Bulgaria; (B.S.B.); (A.P.); (V.M.); (P.T.)
| | - Albena Paskaleva
- Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee Blvd., 1784 Sofia, Bulgaria; (B.S.B.); (A.P.); (V.M.); (P.T.)
| | - Ivalina Avramova
- Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Street, bl. 10, 1113 Sofia, Bulgaria; (I.A.); (P.T.); (D.K.)
| | - Vladimir Mehandhziev
- Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee Blvd., 1784 Sofia, Bulgaria; (B.S.B.); (A.P.); (V.M.); (P.T.)
| | - Peter Tzvetkov
- Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Street, bl. 10, 1113 Sofia, Bulgaria; (I.A.); (P.T.); (D.K.)
| | - Penka Terziyska
- Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee Blvd., 1784 Sofia, Bulgaria; (B.S.B.); (A.P.); (V.M.); (P.T.)
| | - Daniela Kovacheva
- Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Street, bl. 10, 1113 Sofia, Bulgaria; (I.A.); (P.T.); (D.K.)
| | - Massimiliano Polichetti
- Department of Physics ‘E.R. Caianiello’, University of Salerno, via Giovanni Paolo II, 132, Fisciano, I-84084 Salerno, Italy; (A.G.); (M.P.)
- CNR-SPIN Salerno, via Giovanni Paolo II, 132, Fisciano, I-84084 Salerno, Italy
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16
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Zhao M, Guo W, Wu X, Ma L, Song P, Li G, Zhen C, Zhao D, Hou D. Zero-field-cooling exchange bias up to room temperature in the strained kagome antiferromagnet Mn 3.1Sn 0.9. MATERIALS HORIZONS 2023; 10:4597-4608. [PMID: 37593768 DOI: 10.1039/d3mh00754e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/19/2023]
Abstract
Zero-field-cooling exchange bias (ZFC EB) has always been a research hotspot for researchers, because it can realize the movement of the magnetization hysteresis loop along the field axis without field cooling, which greatly expands the universality and convenience of the application of the exchange bias effect. Achieving ZFC EB at room temperature is an ongoing challenge. To this end, a design strategy from the sublattice level is proposed, and a wide temperature range ZFC EB up to room temperature with a vertical magnetization shift is observed in the strained kagome antiferromagnet Mn3.1Sn0.9. Magnetic analysis and first-principles calculations reveal that the ZFC EB arises from the strong exchange interaction between the non-coplanar antiferromagnetic Mn kagome sublattice occupying normal Mn sites and the collinear ferromagnetic Mn sublattice occupying Sn sites. This discovery is of great significance for the application of ZFC EB in antiferromagnetic spintronic devices.
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Affiliation(s)
- Mingyue Zhao
- Hebei Key Laboratory of Photophysics Research and Application, College of Physics, Hebei Normal University, Shijiazhuang, 050024, People's Republic of China.
| | - Wei Guo
- Hebei Key Laboratory of Photophysics Research and Application, College of Physics, Hebei Normal University, Shijiazhuang, 050024, People's Republic of China.
| | - Xian Wu
- Hebei Key Laboratory of Photophysics Research and Application, College of Physics, Hebei Normal University, Shijiazhuang, 050024, People's Republic of China.
| | - Li Ma
- Hebei Key Laboratory of Photophysics Research and Application, College of Physics, Hebei Normal University, Shijiazhuang, 050024, People's Republic of China.
| | - Ping Song
- State Key Laboratory of Metastable Materials Science & Technology and Key Laboratory for Microstructural Material Physics of Hebei Province, School of Science, Yanshan University, Qinhuangdao 066004, People's Republic of China.
| | - Guoke Li
- Hebei Key Laboratory of Photophysics Research and Application, College of Physics, Hebei Normal University, Shijiazhuang, 050024, People's Republic of China.
| | - Congmian Zhen
- Hebei Key Laboratory of Photophysics Research and Application, College of Physics, Hebei Normal University, Shijiazhuang, 050024, People's Republic of China.
| | - Dewei Zhao
- Hebei Key Laboratory of Photophysics Research and Application, College of Physics, Hebei Normal University, Shijiazhuang, 050024, People's Republic of China.
| | - Denglu Hou
- Hebei Key Laboratory of Photophysics Research and Application, College of Physics, Hebei Normal University, Shijiazhuang, 050024, People's Republic of China.
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17
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Yoon JY, Zhang P, Chou CT, Takeuchi Y, Uchimura T, Hou JT, Han J, Kanai S, Ohno H, Fukami S, Liu L. Handedness anomaly in a non-collinear antiferromagnet under spin-orbit torque. NATURE MATERIALS 2023; 22:1106-1113. [PMID: 37537356 DOI: 10.1038/s41563-023-01620-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 06/23/2023] [Indexed: 08/05/2023]
Abstract
Non-collinear antiferromagnets are an emerging family of spintronic materials because they not only possess the general advantages of antiferromagnets but also enable more advanced functionalities. Recently, in an intriguing non-collinear antiferromagnet Mn3Sn, where the octupole moment is defined as the collective magnetic order parameter, spin-orbit torque (SOT) switching has been achieved in seemingly the same protocol as in ferromagnets. Nevertheless, it is fundamentally important to explore the unknown octupole moment dynamics and contrast it with the magnetization vector of ferromagnets. Here we report a handedness anomaly in the SOT-driven dynamics of Mn3Sn: when spin current is injected, the octupole moment rotates in the opposite direction to the individual moments, leading to a SOT switching polarity distinct from ferromagnets. By using second-harmonic and d.c. magnetometry, we track the SOT effect onto the octupole moment during its rotation and reveal that the handedness anomaly stems from the interactions between the injected spin and the unique chiral-spin structure of Mn3Sn. We further establish the torque balancing equation of the magnetic octupole moment and quantify the SOT efficiency. Our finding provides a guideline for understanding and implementing the electrical manipulation of non-collinear antiferromagnets, which in nature differs from the well-established collinear magnets.
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Affiliation(s)
- Ju-Young Yoon
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai, Japan
- Graduate School of Engineering, Tohoku University, Sendai, Japan
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Pengxiang Zhang
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Chung-Tao Chou
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Yutaro Takeuchi
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan
| | - Tomohiro Uchimura
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai, Japan
- Graduate School of Engineering, Tohoku University, Sendai, Japan
| | - Justin T Hou
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Jiahao Han
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai, Japan.
| | - Shun Kanai
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai, Japan
- Graduate School of Engineering, Tohoku University, Sendai, Japan
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, Sendai, Japan
- Division for the Establishment of Frontier Sciences of Organization for Advanced Studies, Tohoku University, Sendai, Japan
| | - Hideo Ohno
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai, Japan
- Graduate School of Engineering, Tohoku University, Sendai, Japan
- WPI-Advanced Institute for Materials Research, 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
| | - Shunsuke Fukami
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai, Japan.
- Graduate School of Engineering, Tohoku University, Sendai, Japan.
- WPI-Advanced Institute for Materials Research, 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.
- Inamori Research Institute for Science, Kyoto, Japan.
| | - Luqiao Liu
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA.
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18
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Del Barco E, Kent AD. A handy way to rotate chiral spins. NATURE MATERIALS 2023; 22:1051-1052. [PMID: 37644226 DOI: 10.1038/s41563-023-01647-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Affiliation(s)
- Enrique Del Barco
- Department of Physics, University of Central Florida, Orlando, FL, USA.
| | - Andrew D Kent
- Center for Quantum Phenomena, Department of Physics, New York University, New York, NY, USA.
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19
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Han J, Cheng R, Liu L, Ohno H, Fukami S. Coherent antiferromagnetic spintronics. NATURE MATERIALS 2023; 22:684-695. [PMID: 36941390 DOI: 10.1038/s41563-023-01492-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 01/25/2023] [Indexed: 06/03/2023]
Abstract
Antiferromagnets have attracted extensive interest as a material platform in spintronics. So far, antiferromagnet-enabled spin-orbitronics, spin-transfer electronics and spin caloritronics have formed the bases of antiferromagnetic spintronics. Spin transport and manipulation based on coherent antiferromagnetic dynamics have recently emerged, pushing the developing field of antiferromagnetic spintronics towards a new stage distinguished by the features of spin coherence. In this Review, we categorize and analyse the critical effects that harness the coherence of antiferromagnets for spintronic applications, including spin pumping from monochromatic antiferromagnetic magnons, spin transmission via phase-correlated antiferromagnetic magnons, electrically induced spin rotation and ultrafast spin-orbit effects in antiferromagnets. We also discuss future opportunities in research and applications stimulated by the principles, materials and phenomena of coherent antiferromagnetic spintronics.
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Affiliation(s)
- Jiahao Han
- Research Institute of Electrical Communication, Tohoku University, Sendai, Japan.
| | - Ran Cheng
- Department of Electrical and Computer Engineering, University of California Riverside, Riverside, CA, USA
- Department of Physics and Astronomy, University of California Riverside, Riverside, CA, USA
| | - Luqiao Liu
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Hideo Ohno
- Research Institute of Electrical Communication, 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
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan
| | - Shunsuke Fukami
- Research Institute of Electrical Communication, 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.
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan.
- Inamori Research Institute of Science, Kyoto, Japan.
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20
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Ding N, Yananose K, Rizza C, Fan FR, Dong S, Stroppa A. Magneto-optical Kerr Effect in Ferroelectric Antiferromagnetic Two-Dimensional Heterostructures. ACS APPLIED MATERIALS & INTERFACES 2023; 15:22282-22290. [PMID: 37078781 DOI: 10.1021/acsami.3c02680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
We studied the magneto-optical Kerr effect (MOKE) of two-dimensional (2D) heterostructure CrI3/In2Se3/CrI3 using density functional theory calculations and symmetry analysis. The spontaneous polarization in the In2Se3 ferroelectric layer and the antiferromagnetic ordering in CrI3 layers break the mirror and the time-reversal symmetry, thus activating MOKE. We show that the Kerr angle can be reversed by either the polarization or the antiferromagnetic order parameter. Our results suggest that ferroelectric and antiferromagnetic 2D heterostructures could be exploited for ultracompact information storage devices, where the information is encoded by the two ferroelectric or the two time-reversed antiferromagnetic states and the read-out is performed optically by MOKE.
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Affiliation(s)
- Ning Ding
- School of Physics, Southeast University, Nanjing, Jiangsu 21189, People's Republic of China
| | - Kunihiro Yananose
- Center for Theoretical Physics, Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
| | - Carlo Rizza
- Department of Physical and Chemical Sciences, University of L'Aquila, Via Vetoio, I-67100 Coppito, L'Aquila, Italy
| | - Feng-Ren Fan
- Department of Physics and Guangdong-Hong Kong Joint Laboratory of Quantum Matter, The University of Hong Kong, Hong Kong, People's Republic of China
| | - Shuai Dong
- School of Physics, Southeast University, Nanjing, Jiangsu 21189, People's Republic of China
| | - Alessandro Stroppa
- Department of Physical and Chemical Sciences, University of L'Aquila, Via Vetoio, I-67100 Coppito, L'Aquila, Italy
- Consiglio Nazionale delle Ricerche, Institute for Superconducting and Innovative Materials and Devices (CNR-SPIN), University of L'Aquila, Via Vetoio, I-67100 Coppito, L'Aquila, Italy
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21
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Li X, Koo J, Zhu Z, Behnia K, Yan B. Field-linear anomalous Hall effect and Berry curvature induced by spin chirality in the kagome antiferromagnet Mn 3Sn. Nat Commun 2023; 14:1642. [PMID: 36964128 PMCID: PMC10039076 DOI: 10.1038/s41467-023-37076-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Accepted: 03/01/2023] [Indexed: 03/26/2023] Open
Abstract
During the past two decades, it has been established that a non-trivial electron wave-function topology generates an anomalous Hall effect (AHE), which shows itself as a Hall conductivity non-linear in magnetic field. Here, we report on an unprecedented case of field-linear AHE. In Mn3Sn, a kagome magnet, the out-of-plane Hall response, which shows an abrupt jump, was discovered to be a case of AHE. We find now that the in-plane Hall response, which is perfectly linear in magnetic field, is set by the Berry curvature of the wavefunction. The amplitude of the Hall response and its concomitant Nernst signal exceed by far what is expected in the semiclassical picture. We argue that magnetic field induces out-of-plane spin canting and thereafter gives rise to nontrivial spin chirality on the kagome lattice. In band structure, we find that the spin chirality modifies the topology by gapping out Weyl nodal lines unknown before, accounting for the AHE observed. Our work reveals intriguing unification of real-space Berry phase from spin chirality and momentum-space Berry curvature in a kagome material.
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Affiliation(s)
- Xiaokang Li
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, China.
| | - Jahyun Koo
- Department of Condensed Matter Physics, Weizmann Institute of Science, 7610001, Rehovot, Israel
| | - Zengwei Zhu
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, China.
| | - Kamran Behnia
- Laboratoire de Physique et d'Étude des Matériaux (ESPCI-CNRS-Sorbonne Université), PSL Research University, 75005, Paris, France
| | - Binghai Yan
- Department of Condensed Matter Physics, Weizmann Institute of Science, 7610001, Rehovot, Israel.
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22
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Xia W, Li C, Zhang S, Wang X, Wang S, Yang Q, Li W, Xiong C, Huang J, Wang Q. Ho-Ion-Polymer/Graphene Heterojunctions Toward Room-Temperature Ferromagnets. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023:e2300385. [PMID: 36929570 DOI: 10.1002/smll.202300385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 02/21/2023] [Indexed: 06/18/2023]
Abstract
Organic ferromagnetic materials offer great promise for spintronic devices, carbon-based chips, and quantum communications, but remain as a challenging issue due to their low saturation magnetization and/or unsustainable ferromagnetic properties. To date, magnetic ion polymers have displayed paramagnetism without exception at room-temperature. In this study, it is reported for the first time that, owing to the structural restriction and charge exchange of Ho ion by polymer/graphene π-π stacking heterojunctions, holmium ion polymer composites exhibited typical hysteresis lines of ferromagnetic materials at room temperature. The room-temperature ferromagnetic ion polymer composite presented the highest saturation magnetization value of 3.36 emu g-1 and unprecedented sustainable ferromagnetism, compared to reported room-temperature organic ferromagnetic materials. Accordingly, prepared ferromagnetic composites also achieved impressive wave absorption properties, with a maximum reflection loss of as much as -57.32 dB and a broad absorption bandwidth of 5.05 GHz. These findings may promote the development of room-temperature organic ferromagnetic materials.
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Affiliation(s)
- Wenlai Xia
- State Key Laboratory of Silicate Materials for Architectures, School of Materials Science and Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, 430070, P. R. China
| | - Chenjian Li
- State Key Laboratory of Silicate Materials for Architectures, School of Materials Science and Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, 430070, P. R. China
| | - Shixian Zhang
- State Key Laboratory of Silicate Materials for Architectures, School of Materials Science and Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, 430070, P. R. China
| | - Xuelin Wang
- State Key Laboratory of Silicate Materials for Architectures, School of Materials Science and Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, 430070, P. R. China
| | - Shan Wang
- State Key Laboratory of Silicate Materials for Architectures, School of Materials Science and Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, 430070, P. R. China
| | - Quanling Yang
- State Key Laboratory of Silicate Materials for Architectures, School of Materials Science and Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, 430070, P. R. China
| | - Wei Li
- State Key Laboratory of Silicate Materials for Architectures, School of Materials Science and Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, 430070, P. R. China
| | - Chuanxi Xiong
- State Key Laboratory of Silicate Materials for Architectures, School of Materials Science and Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, 430070, P. R. China
| | - Jing Huang
- State Key Laboratory for New Textile Materials & Advanced Processing Technology, School of Materials Science and Engineering, Wuhan Textile University, Sunshine Avenue 1, Wuhan, 430200, P. R. China
| | - Qing Wang
- State Key Laboratory of Silicate Materials for Architectures, School of Materials Science and Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, 430070, P. R. China
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania, 16802, USA
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23
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Damasceno GHB, Carvalho WOF, Cerqueira Sodré A, Oliveira ON, Mejía-Salazar JR. Magnetoplasmonic Nanoantennas for On-Chip Reconfigurable Optical Wireless Communications. ACS APPLIED MATERIALS & INTERFACES 2023; 15:8617-8623. [PMID: 36689678 DOI: 10.1021/acsami.2c19376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
On-chip wireless communications require optical nanoantennas with dynamically tunable radiation patterns, which may allow for higher integration with multiple nanoantennas instead of two fixed nanoantennas in existing approaches. In this paper, we introduce a concept to enable active manipulation of radiated beam steering using applied magnetic fields. The proposed system consists of a highly directive Yagi-Uda-like arrangement of magnetoplasmonic nanoribs made of Co6Ag94 and immersed in SiO2. Numerical demonstration of the tilting of the radiated beam from the nanoantenna on its plane is provided with full-wave electromagnetic simulations using the finite element method. The tilt direction of the radiated beam can be changed by reversing the magnetization direction, while the conventional plasmonic nanoantenna pattern is recovered by demagnetizing the system. The geometry of the nanoantenna can be tailored to work at optical or infrared wavelengths, but a proof of concept for λ = 700 nm is conducted for taking advantage of the high magneto-optical activity of Co6Ag94. The design was based on experimental data for materials that can be fabricated via nanolithography, thus permitting magnetically on-chip reconfigurable optical wireless communications.
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Affiliation(s)
- Gabriel H B Damasceno
- National Institute of Telecommunications (Inatel), Santa Rita do Sapucaí37540-000, MG, Brazil
| | - William O F Carvalho
- National Institute of Telecommunications (Inatel), Santa Rita do Sapucaí37540-000, MG, Brazil
| | - Arismar Cerqueira Sodré
- National Institute of Telecommunications (Inatel), Santa Rita do Sapucaí37540-000, MG, Brazil
| | - Osvaldo N Oliveira
- Sao Carlos Institute of Physics, University of Sao Paulo, CP 369, Sao Carlos13560-970, SP, Brazil
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24
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Shah SQA, Annaorazov M, Rimal G, Wang J, Borunda MF, Tang J, Yost AJ. Controlling the Magneto-Optical Response in Ultrathin Films of EuO 1-x via Interface Engineering with Ferroelectric BaTi 2O 5. ACS APPLIED MATERIALS & INTERFACES 2023; 15:10141-10149. [PMID: 36774653 DOI: 10.1021/acsami.2c18842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Utilizing pulsed laser deposition, a film of EuO1-x was deposited onto a Si(001) substrate with MgO buffer and compared to the same heterostructure with an additional BaTi2O5 thin film on top of the EuO1-x surface. X-ray diffraction (XRD) indicates the films crystallize into a preferred EuO(111) orientation; it also reveals the clear presence of EuSi2, which suggests Si or Eu diffuses across the MgO buffer layer. EuO1-x films exhibit a ferromagnetic (FM) signature and temperature-dependent exchange bias, indicated by MOKE measurements, suggesting the presence of a magnetic order well above the EuO Curie temperature with possible origins in charge carrier density near the interface. In comparison, an antiferromagnetic character persists well above the EuO Curie temperature of 69 K and the enhanced Curie temperature of 150 K for BaTi2O5 films grown on the EuO1-x films. The antiferromagnetic behavior is not seen in thicker EuO1-x thin films when integrated with other ferroelectric (FE) phases of the BaO-TiO2 system, suggesting an origin in the perturbed charge population at the BaTi2O5/EuO1-x interface.
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Affiliation(s)
- Syed Q A Shah
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588 United States
| | - Muhammet Annaorazov
- Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078-3072 United States
| | - Gaurab Rimal
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854 United States
- Department of Physics and Astronomy, University of Wyoming, Laramie, Wyoming 82071 United States
| | - Jian Wang
- Canadian Light Source Inc., 44 Innovation Boulevard, Saskatoon, Saskatchewan S7N 2V3, Canada
| | - Mario F Borunda
- Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078-3072 United States
| | - Jinke Tang
- Department of Physics and Astronomy, University of Wyoming, Laramie, Wyoming 82071 United States
| | - Andrew J Yost
- Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078-3072 United States
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25
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Wang X, Zhou X, Yan H, Qin P, Chen H, Meng Z, Feng Z, Liu L, Liu Z. Topological Hall Effect in Thin Films of an Antiferromagnetic Weyl Semimetal Integrated on Si. ACS APPLIED MATERIALS & INTERFACES 2023; 15:7572-7577. [PMID: 36700918 DOI: 10.1021/acsami.2c20644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Since the large room-temperature anomalous Hall effect was discovered in noncollinear antiferromagnets, Mn3Sn has received immense research interest as it exhibits abundant exotic physical properties including Weyl points and enormous potential for antiferromagnetic spintronic device applications. In this work, we report the emergence of the topological Hall effect in Mn3Sn films grown on Si that is the workhorse for the modern highly integrated information technology. Importantly, through a series of systematic comparative experiments, the intriguing topological Hall effect phenomenon related to the appearance of the noncoplanar chiral spin structure is found to be induced by the Mn3Sn/SiO2 interface. Furthermore, it was found that the current injection to a Pt/Mn3Sn bilayer Hall bar device can effectively manipulate the chiral spin structure of Mn3Sn, which demonstrates the feasibility of Si-based noncollinear antiferromagnetic spintronics.
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Affiliation(s)
- Xiaoning Wang
- School of Materials Science and Engineering, Beihang University, Beijing 100191, China
| | - Xiaorong Zhou
- School of Materials Science and Engineering, Beihang University, Beijing 100191, China
| | - Han Yan
- School of Materials Science and Engineering, Beihang University, Beijing 100191, China
| | - Peixin Qin
- School of Materials Science and Engineering, Beihang University, Beijing 100191, China
| | - Hongyu Chen
- School of Materials Science and Engineering, Beihang University, Beijing 100191, China
| | - Ziang Meng
- School of Materials Science and Engineering, Beihang University, Beijing 100191, China
| | - Zexin Feng
- School of Materials Science and Engineering, Beihang University, Beijing 100191, China
| | - Li Liu
- School of Materials Science and Engineering, Beihang University, Beijing 100191, China
| | - Zhiqi Liu
- School of Materials Science and Engineering, Beihang University, Beijing 100191, China
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26
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Chen X, Higo T, Tanaka K, Nomoto T, Tsai H, Idzuchi H, Shiga M, Sakamoto S, Ando R, Kosaki H, Matsuo T, Nishio-Hamane D, Arita R, Miwa S, Nakatsuji S. Octupole-driven magnetoresistance in an antiferromagnetic tunnel junction. Nature 2023; 613:490-495. [PMID: 36653566 PMCID: PMC9849134 DOI: 10.1038/s41586-022-05463-w] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 10/19/2022] [Indexed: 01/19/2023]
Abstract
The tunnelling electric current passing through a magnetic tunnel junction (MTJ) is strongly dependent on the relative orientation of magnetizations in ferromagnetic electrodes sandwiching an insulating barrier, rendering efficient readout of spintronics devices1-5. Thus, tunnelling magnetoresistance (TMR) is considered to be proportional to spin polarization at the interface1 and, to date, has been studied primarily in ferromagnets. Here we report observation of TMR in an all-antiferromagnetic tunnel junction consisting of Mn3Sn/MgO/Mn3Sn (ref. 6). We measured a TMR ratio of around 2% at room temperature, which arises between the parallel and antiparallel configurations of the cluster magnetic octupoles in the chiral antiferromagnetic state. Moreover, we carried out measurements using a Fe/MgO/Mn3Sn MTJ and show that the sign and direction of anisotropic longitudinal spin-polarized current in the antiferromagnet7 can be controlled by octupole direction. Strikingly, the TMR ratio (about 2%) of the all-antiferromagnetic MTJ is much larger than that estimated using the observed spin polarization. Theoretically, we found that the chiral antiferromagnetic MTJ may produce a substantially large TMR ratio as a result of the time-reversal, symmetry-breaking polarization characteristic of cluster magnetic octupoles. Our work lays the foundation for the development of ultrafast and efficient spintronic devices using antiferromagnets8-10.
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Affiliation(s)
- Xianzhe Chen
- Department of Physics, University of Tokyo, Tokyo, Japan.,Institute for Solid State Physics, University of Tokyo, Chiba, Japan
| | - Tomoya Higo
- Department of Physics, University of Tokyo, Tokyo, Japan.,Institute for Solid State Physics, University of Tokyo, Chiba, Japan.,CREST, Japan Science and Technology Agency, Saitama, Japan
| | - Katsuhiro Tanaka
- Research Center for Advanced Science and Technology, University of Tokyo, Tokyo, Japan
| | - Takuya Nomoto
- Research Center for Advanced Science and Technology, University of Tokyo, Tokyo, Japan.,PRESTO, Japan Science and Technology Agency, Saitama, Japan
| | - Hanshen Tsai
- Department of Physics, University of Tokyo, Tokyo, Japan.,Institute for Solid State Physics, University of Tokyo, Chiba, Japan
| | - Hiroshi Idzuchi
- Department of Physics, University of Tokyo, Tokyo, Japan.,Institute for Solid State Physics, University of Tokyo, Chiba, Japan
| | - Masanobu Shiga
- Institute for Solid State Physics, University of Tokyo, Chiba, Japan
| | - Shoya Sakamoto
- Institute for Solid State Physics, University of Tokyo, Chiba, Japan
| | - Ryoya Ando
- Institute for Solid State Physics, University of Tokyo, Chiba, Japan
| | - Hidetoshi Kosaki
- Institute for Solid State Physics, University of Tokyo, Chiba, Japan
| | - Takumi Matsuo
- Department of Physics, University of Tokyo, Tokyo, Japan
| | | | - Ryotaro Arita
- CREST, Japan Science and Technology Agency, Saitama, Japan.,Research Center for Advanced Science and Technology, University of Tokyo, Tokyo, Japan.,RIKEN, Center for Emergent Matter Science, Saitama, Japan
| | - Shinji Miwa
- Institute for Solid State Physics, University of Tokyo, Chiba, Japan.,CREST, Japan Science and Technology Agency, Saitama, Japan.,Trans-scale Quantum Science Institute, University of Tokyo, Tokyo, Japan
| | - Satoru Nakatsuji
- Department of Physics, University of Tokyo, Tokyo, Japan. .,Institute for Solid State Physics, University of Tokyo, Chiba, Japan. .,CREST, Japan Science and Technology Agency, Saitama, Japan. .,Trans-scale Quantum Science Institute, University of Tokyo, Tokyo, Japan. .,Canadian Institute for Advanced Research, Toronto, Ontario, Canada.
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27
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Zhao X, Li W, Xia Q, Lu P, Tao H, Xia M, Zhang X, Zhao X, Xu Y. High Verdet Constant Glass for Magnetic Field Sensors. ACS APPLIED MATERIALS & INTERFACES 2022; 14:57028-57036. [PMID: 36519737 DOI: 10.1021/acsami.2c18119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Due to the high transparency, high Verdet constant, as well as easy processing properties, rare-earth ion-doped glasses have demonstrated great potential in magneto-optical (MO) applications. However, the variation in the valence state of rare-earth ions (Tb3+ to Tb4+) resulted in the decreased effective concentration of the paramagnetic ions and thus degraded MO performance. Here, a strategy was proposed to inhibit the oxidation of Tb3+ into Tb4+ as well as improve the thermal stability by tuning the optical basicity of glass networks. Moreover, the depolymerization of the glass network was modulated to accommodate more Tb ions. Thus, a record high effective concentration (14.19 × 1021/cm3) of Tb ions in glass was achieved, generating a high Verdet constant of 113 rad/(T·m) at 650 nm. Lastly, the first application of MO glass for magnetic field sensors was demonstrated, achieving a sensitivity of 0.139 rad/T. We hope our work provides guidance for the fabrication of MO glass with high performance and thermal stability and could push MO glass one step further for magnetic sensing applications.
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Affiliation(s)
- Xudong Zhao
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, China
| | - Weiwei Li
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430074, China
| | - Qi Xia
- School of Intelligent Manufacturing and Electronic Engineering, Wenzhou University of Technology, Wenzhou 325035, China
| | - Ping Lu
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, China
| | - Haizheng Tao
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, China
| | - Mengling Xia
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, China
| | - Xianghua Zhang
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, China
- Institut Des Sciences Chimiques de Rennes UMR 6226, CNRS, Université de Rennes 1, Rennes 35042, France
| | - Xiujian Zhao
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, China
| | - Yinsheng Xu
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, China
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28
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Abstract
A kagome lattice naturally features Dirac fermions, flat bands and van Hove singularities in its electronic structure. The Dirac fermions encode topology, flat bands favour correlated phenomena such as magnetism, and van Hove singularities can lead to instabilities towards long-range many-body orders, altogether allowing for the realization and discovery of a series of topological kagome magnets and superconductors with exotic properties. Recent progress in exploring kagome materials has revealed rich emergent phenomena resulting from the quantum interactions between geometry, topology, spin and correlation. Here we review these key developments in this field, starting from the fundamental concepts of a kagome lattice, to the realizations of Chern and Weyl topological magnetism, to various flat-band many-body correlations, and then to the puzzles of unconventional charge-density waves and superconductivity. We highlight the connection between theoretical ideas and experimental observations, and the bond between quantum interactions within kagome magnets and kagome superconductors, as well as their relation to the concepts in topological insulators, topological superconductors, Weyl semimetals and high-temperature superconductors. These developments broadly bridge topological quantum physics and correlated many-body physics in a wide range of bulk materials and substantially advance the frontier of topological quantum matter.
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29
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Paskaleva A, Buchkov K, Galluzzi A, Spassov D, Blagoev B, Ivanov T, Mehandzhiev V, Avramova IA, Terzyiska P, Tzvetkov P, Kovacheva D, Polichetti M. Magneto-Optical and Muliferroic Properties of Transition-Metal (Fe, Co, or Ni)-Doped ZnO Layers Deposited by ALD. ACS OMEGA 2022; 7:43306-43315. [PMID: 36467919 PMCID: PMC9713891 DOI: 10.1021/acsomega.2c06240] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 11/03/2022] [Indexed: 06/17/2023]
Abstract
ZnO doped with transition metals (Co, Fe, or Ni) that have non-compensated electron spins attracts particular interest as it can induce various magnetic phenomena and behaviors. The advanced atomic layer deposition (ALD) technique makes it possible to obtain very thin layers of doped ZnO with controllable thicknesses and compositions that are compatible with the main microelectronic technologies, which further boosts the interest. The present study provides an extended analysis of the magneto-optical MO Kerr effect and the dielectric properties of (Co, Fe, or Ni)-doped ZnO films prepared by ALD. The structural, magneto-optical, and dielectric properties were considered in relation to the technological details of the ALD process and the corresponding dopant effects. All doped samples show a strong MO Kerr behavior with a substantial magnetization response and very high values of the Kerr polarization angle, especially in the case of ZnO/Fe. In addition, the results give evidence that Fe-doped ZnO also demonstrates a ferroelectric behavior. In this context, the observed rich and versatile physical nature and functionality open up new prospects for the application of these nanostructured materials in advanced electronic, spintronic, and optical devices.
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Affiliation(s)
- Albena Paskaleva
- Institute
of Solid State Physics, Bulgarian Academy
of Sciences, 72 Tsarigradsko
Chaussee Blvd., Sofia1784, Bulgaria
| | - Krastyo Buchkov
- Institute
of Solid State Physics, Bulgarian Academy
of Sciences, 72 Tsarigradsko
Chaussee Blvd., Sofia1784, Bulgaria
- Institute
of Optical Materials and Technologies, Bulgarian
Academy of Sciences, Acad. G. Bonchev Str, Bl.109, SofiaBG-1113, Bulgaria
| | - Armando Galluzzi
- Department
of Physics “E.R. Caianiello”, University of Salerno, via Giovanni Paolo II, 132, Fisciano (SALERNO)I-84084, Italy
- CNR-SPIN
Salerno, via Giovanni
Paolo II, 132, Fisciano (SALERNO)I-84084, Italy
| | - Dencho Spassov
- Institute
of Solid State Physics, Bulgarian Academy
of Sciences, 72 Tsarigradsko
Chaussee Blvd., Sofia1784, Bulgaria
| | - Blagoy Blagoev
- Institute
of Solid State Physics, Bulgarian Academy
of Sciences, 72 Tsarigradsko
Chaussee Blvd., Sofia1784, Bulgaria
| | - Tzvetan Ivanov
- Institute
of Solid State Physics, Bulgarian Academy
of Sciences, 72 Tsarigradsko
Chaussee Blvd., Sofia1784, Bulgaria
| | - Vladimir Mehandzhiev
- Institute
of Solid State Physics, Bulgarian Academy
of Sciences, 72 Tsarigradsko
Chaussee Blvd., Sofia1784, Bulgaria
| | - Ivalina Avramova Avramova
- Institute
of General and Inorganic Chemistry, Bulgarian
Academy of Sciences, Acad. G. Bonchev Str., Bl.10, SofiaBG-1113Bulgaria
| | - Penka Terzyiska
- Institute
of Solid State Physics, Bulgarian Academy
of Sciences, 72 Tsarigradsko
Chaussee Blvd., Sofia1784, Bulgaria
| | - Peter Tzvetkov
- Institute
of General and Inorganic Chemistry, Bulgarian
Academy of Sciences, Acad. G. Bonchev Str., Bl.10, SofiaBG-1113Bulgaria
| | - Daniela Kovacheva
- Institute
of General and Inorganic Chemistry, Bulgarian
Academy of Sciences, Acad. G. Bonchev Str., Bl.10, SofiaBG-1113Bulgaria
| | - Massimiliano Polichetti
- Department
of Physics “E.R. Caianiello”, University of Salerno, via Giovanni Paolo II, 132, Fisciano (SALERNO)I-84084, Italy
- CNR-SPIN
Salerno, via Giovanni
Paolo II, 132, Fisciano (SALERNO)I-84084, Italy
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30
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Song J, Oh T, Ko EK, Lee JH, Kim WJ, Zhu Y, Yang BJ, Li Y, Noh TW. Higher harmonics in planar Hall effect induced by cluster magnetic multipoles. Nat Commun 2022; 13:6501. [PMID: 36310175 PMCID: PMC9618580 DOI: 10.1038/s41467-022-34189-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 10/13/2022] [Indexed: 11/11/2022] Open
Abstract
Antiferromagnetic (AFM) materials are attracting tremendous attention due to their spintronic applications and associated novel topological phenomena. However, detecting and identifying the spin configurations in AFM materials are quite challenging due to the absence of net magnetization. Herein, we report the practicality of utilizing the planar Hall effect (PHE) to detect and distinguish “cluster magnetic multipoles” in AFM Nd2Ir2O7 (NIO-227) fully strained films. By imposing compressive strain on the spin structure of NIO-227, we artificially induced cluster magnetic multipoles, namely dipoles and A2- and T1-octupoles. Importantly, under magnetic field rotation, each magnetic multipole exhibits distinctive harmonics of the PHE oscillation. Moreover, the planar Hall conductivity has a nonlinear magnetic field dependence, which can be attributed to the magnetic response of the cluster magnetic octupoles. Our work provides a strategy for identifying cluster magnetic multipoles in AFM systems and would promote octupole-based AFM spintronics. The lack of net magnetization in antiferromagnets makes them technologically promising, but it also makes detecting the spin orders challenging. Here, using electrical transport measurement, Song et al show how the planar Hall effect can detect different cluster magnetic multipoles in antiferromagnetic Nd2Ir2O7 film.
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31
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Xie H, Chen X, Zhang Q, Mu Z, Zhang X, Yan B, Wu Y. Magnetization switching in polycrystalline Mn 3Sn thin film induced by self-generated spin-polarized current. Nat Commun 2022; 13:5744. [PMID: 36180425 PMCID: PMC9525633 DOI: 10.1038/s41467-022-33345-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 09/13/2022] [Indexed: 11/13/2022] Open
Abstract
Electrical manipulation of spins is essential to design state-of-the-art spintronic devices and commonly relies on the spin current injected from a second heavy-metal material. The fact that chiral antiferromagnets produce spin current inspires us to explore the magnetization switching of chiral spins using self-generated spin torque. Here, we demonstrate the electric switching of noncollinear antiferromagnetic state in Mn3Sn by observing a crossover from conventional spin-orbit torque to the self-generated spin torque when increasing the MgO thickness in Ta/MgO/Mn3Sn polycrystalline films. The spin current injection from the Ta layer can be controlled and even blocked by varying the MgO thickness, but the switching sustains even at a large MgO thickness. Furthermore, the switching polarity reverses when the MgO thickness exceeds around 3 nm, which cannot be explained by the spin-orbit torque scenario due to spin current injection from the Ta layer. Evident current-induced switching is also observed in MgO/Mn3Sn and Ti/Mn3Sn bilayers, where external injection of spin Hall current to Mn3Sn is negligible. The inter-grain spin-transfer torque induced by spin-polarized current explains the experimental observations. Our findings provide an alternative pathway for electrical manipulation of non-collinear antiferromagnetic state without resorting to the conventional bilayer structure. Under an applied current, chiral antiferromagnets, such as Mn3Sn, can produce a spin-polarized current. Here, by varying the thickness of a buffering layer, the authors show that this spin-polarized current can drive self-induced switching in polycrystalline Mn3Sn.
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Affiliation(s)
- Hang Xie
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117583, Singapore
| | - Xin Chen
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117583, Singapore
| | - Qi Zhang
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117583, Singapore.,Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Xueyuan Rd. 1088, Shenzhen, 518055, China
| | - Zhiqiang Mu
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, China
| | - Xinhai Zhang
- Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Xueyuan Rd. 1088, Shenzhen, 518055, China
| | - Binghai Yan
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, 7610001, Israel.
| | - Yihong Wu
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117583, Singapore.
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32
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Go D, Sallermann M, Lux FR, Blügel S, Gomonay O, Mokrousov Y. Noncollinear Spin Current for Switching of Chiral Magnetic Textures. PHYSICAL REVIEW LETTERS 2022; 129:097204. [PMID: 36083678 DOI: 10.1103/physrevlett.129.097204] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 06/10/2022] [Accepted: 07/25/2022] [Indexed: 06/15/2023]
Abstract
We propose a concept of noncollinear spin current, whose spin polarization varies in space even in nonmagnetic crystals. While it is commonly assumed that the spin polarization of the spin Hall current is uniform, asymmetric local crystal potential generally allows the spin polarization to be noncollinear in space. Based on microscopic considerations, we demonstrate that such noncollinear spin Hall currents can be observed, for example, in layered Kagome Mn_{3}X (X=Ge, Sn) compounds. Moreover, by referring to atomistic spin dynamics simulations we show that noncollinear spin currents can be used to switch the chiral spin texture of Mn_{3}X in a deterministic way even in the absence of an external magnetic field. Our theoretical prediction can be readily tested in experiments, which will open a novel route toward electric control of complex spin structures in noncollinear antiferromagnets.
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Affiliation(s)
- Dongwook Go
- Peter Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, 52425 Jülich, Germany
- Institute of Physics, Johannes Gutenberg University Mainz, 55099 Mainz, Germany
| | - Moritz Sallermann
- Peter Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, 52425 Jülich, Germany
- Science Institute and Faculty of Physical Sciences, University of Iceland, VR-III, 107 Reykjavík, Iceland
| | - Fabian R Lux
- Institute of Physics, Johannes Gutenberg University Mainz, 55099 Mainz, Germany
| | - Stefan Blügel
- Peter Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, 52425 Jülich, Germany
| | - Olena Gomonay
- Institute of Physics, Johannes Gutenberg University Mainz, 55099 Mainz, Germany
| | - Yuriy Mokrousov
- Peter Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, 52425 Jülich, Germany
- Institute of Physics, Johannes Gutenberg University Mainz, 55099 Mainz, Germany
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Choi E, Sim KI, Burch KS, Lee YH. Emergent Multifunctional Magnetic Proximity in van der Waals Layered Heterostructures. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2200186. [PMID: 35596612 PMCID: PMC9313546 DOI: 10.1002/advs.202200186] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 04/01/2022] [Indexed: 05/10/2023]
Abstract
Proximity effect, which is the coupling between distinct order parameters across interfaces of heterostructures, has attracted immense interest owing to the customizable multifunctionalities of diverse 3D materials. This facilitates various physical phenomena, such as spin order, charge transfer, spin torque, spin density wave, spin current, skyrmions, and Majorana fermions. These exotic physics play important roles for future spintronic applications. Nevertheless, several fundamental challenges remain for effective applications: unavoidable disorder and lattice mismatch limits in the growth process, short characteristic length of proximity, magnetic fluctuation in ultrathin films, and relatively weak spin-orbit coupling (SOC). Meanwhile, the extensive library of atomically thin, 2D van der Waals (vdW) layered materials, with unique characteristics such as strong SOC, magnetic anisotropy, and ultraclean surfaces, offers many opportunities to tailor versatile and more effective functionalities through proximity effects. Here, this paper focuses on magnetic proximity, i.e., proximitized magnetism and reviews the engineering of magnetism-related functionalities in 2D vdW layered heterostructures for next-generation electronic and spintronic devices. The essential factors of magnetism and interfacial engineering induced by magnetic layers are studied. The current limitations and future challenges associated with magnetic proximity-related physics phenomena in 2D heterostructures are further discussed.
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Affiliation(s)
- Eun‐Mi Choi
- Center for Integrated Nanostructure Physics, Institute for Basic Science (IBS)Sungkyunkwan University (SKKU)Suwon16419Republic of Korea
| | - Kyung Ik Sim
- Center for Integrated Nanostructure Physics, Institute for Basic Science (IBS)Sungkyunkwan University (SKKU)Suwon16419Republic of Korea
| | - Kenneth S. Burch
- Department of PhysicsBoston College140 Commonwealth AveChestnut HillMA02467‐3804USA
| | - Young Hee Lee
- Center for Integrated Nanostructure Physics, Institute for Basic Science (IBS)Sungkyunkwan University (SKKU)Suwon16419Republic of Korea
- Department of Energy ScienceSungkyunkwan UniversitySuwon16419Republic of Korea
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Perpendicular full switching of chiral antiferromagnetic order by current. Nature 2022; 607:474-479. [PMID: 35859198 DOI: 10.1038/s41586-022-04864-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 05/12/2022] [Indexed: 11/09/2022]
Abstract
Electrical control of a magnetic state of matter lays the foundation for information technologies and for understanding of spintronic phenomena. Spin-orbit torque provides an efficient mechanism for the electrical manipulation of magnetic orders1-11. In particular, spin-orbit torque switching of perpendicular magnetization in nanoscale ferromagnetic bits has enabled the development of stable, reliable and low-power memories and computation12-14. Likewise, for antiferromagnetic spintronics, electrical bidirectional switching of an antiferromagnetic order in a perpendicular geometry may have huge impacts, given its potential advantage for high-density integration and ultrafast operation15,16. Here we report the experimental realization of perpendicular and full spin-orbit torque switching of an antiferromagnetic binary state. We use the chiral antiferromagnet Mn3Sn (ref. 17), which exhibits the magnetization-free anomalous Hall effect owing to a ferroic order of a cluster magnetic octupole hosted in its chiral antiferromagnetic state18. We fabricate heavy-metal/Mn3Sn heterostructures by molecular beam epitaxy and introduce perpendicular magnetic anisotropy of the octupole using an epitaxial in-plane tensile strain. By using the anomalous Hall effect as the readout, we demonstrate 100 per cent switching of the perpendicular octupole polarization in a 30-nanometre-thick Mn3Sn film with a small critical current density of less than 15 megaamperes per square centimetre. Our theory reveals that the perpendicular geometry between the polarization directions of current-induced spin accumulation and of the octupole persistently maximizes the spin-orbit torque efficiency during the deterministic bidirectional switching process. Our work provides a significant basis for antiferromagnetic spintronics.
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Pal B, Hazra BK, Göbel B, Jeon JC, Pandeya AK, Chakraborty A, Busch O, Srivastava AK, Deniz H, Taylor JM, Meyerheim H, Mertig I, Yang SH, Parkin SSP. Setting of the magnetic structure of chiral kagome antiferromagnets by a seeded spin-orbit torque. SCIENCE ADVANCES 2022; 8:eabo5930. [PMID: 35704587 PMCID: PMC9200275 DOI: 10.1126/sciadv.abo5930] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 04/29/2022] [Indexed: 06/03/2023]
Abstract
The current-induced spin-orbit torque switching of ferromagnets has had huge impact in spintronics. However, short spin-diffusion lengths limit the thickness of switchable ferromagnetic layers, thereby limiting their thermal stability. Here, we report a previously unobserved seeded spin-orbit torque (SSOT) by which current can set the magnetic states of even thick layers of the chiral kagome antiferromagnet Mn3Sn. The mechanism involves setting the orientation of the antiferromagnetic domains in a thin region at the interface with spin currents arising from an adjacent heavy metal while also heating the layer above its magnetic ordering temperature. This interface region seeds the resulting spin texture of the entire layer as it cools down and, thereby, overcomes the thickness limitation of conventional spin-orbit torques. SSOT switching in Mn3Sn can be extended beyond chiral antiferromagnets to diverse magnetic systems and provides a path toward the development of highly efficient, high-speed, and thermally stable spintronic devices.
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Affiliation(s)
- Banabir Pal
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany
| | - Binoy K. Hazra
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany
| | - Börge Göbel
- Institute of Physics, Martin Luther University Halle-Wittenberg, 06099 Halle, Germany
| | - Jae-Chun Jeon
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany
| | - Avanindra K. Pandeya
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany
| | - Anirban Chakraborty
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany
| | - Oliver Busch
- Institute of Physics, Martin Luther University Halle-Wittenberg, 06099 Halle, Germany
| | - Abhay K. Srivastava
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany
| | - Hakan Deniz
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany
| | - James M. Taylor
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany
| | - Holger Meyerheim
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany
| | - Ingrid Mertig
- Institute of Physics, Martin Luther University Halle-Wittenberg, 06099 Halle, Germany
| | - See-Hun Yang
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany
| | - Stuart S. P. Parkin
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany
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Progress and prospects in magnetic topological materials. Nature 2022; 603:41-51. [PMID: 35236973 DOI: 10.1038/s41586-021-04105-x] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 10/06/2021] [Indexed: 11/09/2022]
Abstract
Magnetic topological materials represent a class of compounds with properties that are strongly influenced by the topology of their electronic wavefunctions coupled with the magnetic spin configuration. Such materials can support chiral electronic channels of perfect conduction, and can be used for an array of applications, from information storage and control to dissipationless spin and charge transport. Here we review the theoretical and experimental progress achieved in the field of magnetic topological materials, beginning with the theoretical prediction of the quantum anomalous Hall effect without Landau levels, and leading to the recent discoveries of magnetic Weyl semimetals and antiferromagnetic topological insulators. We outline recent theoretical progress that has resulted in the tabulation of, for the first time, all magnetic symmetry group representations and topology. We describe several experiments realizing Chern insulators, Weyl and Dirac magnetic semimetals, and an array of axionic and higher-order topological phases of matter, and we survey future perspectives.
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Chen T, Minami S, Sakai A, Wang Y, Feng Z, Nomoto T, Hirayama M, Ishii R, Koretsune T, Arita R, Nakatsuji S. Large anomalous Nernst effect and nodal plane in an iron-based kagome ferromagnet. SCIENCE ADVANCES 2022; 8:eabk1480. [PMID: 35030028 PMCID: PMC8759748 DOI: 10.1126/sciadv.abk1480] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 11/22/2021] [Indexed: 05/22/2023]
Abstract
Anomalous Nernst effect (ANE), converting a heat flow to transverse electric voltage, originates from the Berry phase of electronic wave function near the Fermi energy EF. Thus, the ANE provides a sensitive probe to detect a topological state that produces large Berry curvature. In addition, a magnet that exhibits a large ANE using low-cost and safe elements will be useful to develop a novel energy harvesting technology. Here, we report our observation of a high ANE exceeding 3 microvolts per kelvin above room temperature in the kagome ferromagnet Fe3Sn with the Curie temperature of 760 kelvin. Our theoretical analysis clarifies that a “nodal plane” produces a flat hexagonal frame with strongly enhanced Berry curvature, resulting in the large ANE. Our discovery of the large ANE in Fe3Sn opens the path for the previously unexplored functionality of flat degenerate electronic states and for developing flexible film thermopile and heat current sensors.
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Affiliation(s)
- Taishi Chen
- Department of Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan
- School of Physics, Southeast University, Nanjing 211189, China
| | - Susumu Minami
- Department of Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Akito Sakai
- Department of Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan
- CREST, Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
| | - Yangming Wang
- Department of Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Zili Feng
- Department of Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan
| | - Takuya Nomoto
- Department of Applied Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Motoaki Hirayama
- Department of Applied Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
- RIKEN Center for Emergent Matter Science (CEMS), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Rieko Ishii
- Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan
| | - Takashi Koretsune
- Department of Physics, Tohoku University, 6-3 Aza-Aoba, Aramaki, Aoba-ku, Sendai 980-8578, Japan
- Center for Science and Innovation in Spintronics (CSIS), Tohoku University, Miyagi, Japan
| | - Ryotaro Arita
- CREST, Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
- Department of Applied Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
- RIKEN Center for Emergent Matter Science (CEMS), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Satoru Nakatsuji
- Department of Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan
- CREST, Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
- Trans-scale Quantum Science Institute, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Institute for Quantum Matter and Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA
- Corresponding author.
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Giant field-like torque by the out-of-plane magnetic spin Hall effect in a topological antiferromagnet. Nat Commun 2021; 12:6491. [PMID: 34795211 PMCID: PMC8602386 DOI: 10.1038/s41467-021-26453-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Accepted: 09/27/2021] [Indexed: 12/03/2022] Open
Abstract
Spin-orbit torques (SOT) enable efficient electrical control of the magnetic state of ferromagnets, ferrimagnets and antiferromagnets. However, the conventional SOT has severe limitation that only in-plane spins accumulate near the surface, whether interpreted as a spin Hall effect (SHE) or as an Edelstein effect. Such a SOT is not suitable for controlling perpendicular magnetization, which would be more beneficial for realizing low-power-consumption memory devices. Here we report the observation of a giant magnetic-field-like SOT in a topological antiferromagnet Mn3Sn, whose direction and size can be tuned by changing the order parameter direction of the antiferromagnet. To understand the magnetic SHE (MSHE)- and the conventional SHE-induced SOTs on an equal footing, we formulate them as interface spin-electric-field responses and analyzed using a macroscopic symmetry analysis and a complementary microscopic quantum kinetic theory. In this framework, the large out-of-plane spin accumulation due to the MSHE has an inter-band origin and is likely to be caused by the large momentum-dependent spin splitting in Mn3Sn. Our work demonstrates the unique potential of antiferromagnetic Weyl semimetals in overcoming the limitations of conventional SOTs and in realizing low-power spintronics devices with new functionalities. Conventional spin-orbit torque (SOT) enables electrical control of in-plane spins, not suitable for perpendicular magnetization. Here, the authors observe a large magnetic-field-like SOT due to a large out-of-plane spin accumulation in topological antiferromagnet Mn3Sn.
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You Y, Bai H, Feng X, Fan X, Han L, Zhou X, Zhou Y, Zhang R, Chen T, Pan F, Song C. Cluster magnetic octupole induced out-of-plane spin polarization in antiperovskite antiferromagnet. Nat Commun 2021; 12:6524. [PMID: 34764284 PMCID: PMC8585975 DOI: 10.1038/s41467-021-26893-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 10/26/2021] [Indexed: 11/09/2022] Open
Abstract
Out-of-plane spin polarization σz has attracted increasing interests of researchers recently, due to its potential in high-density and low-power spintronic devices. Noncollinear antiferromagnet (AFM), which has unique 120° triangular spin configuration, has been discovered to possess σz. However, the physical origin of σz in noncollinear AFM is still not clear, and the external magnetic field-free switching of perpendicular magnetic layer using the corresponding σz has not been reported yet. Here, we use the cluster magnetic octupole in antiperovskite AFM Mn3SnN to demonstrate the generation of σz. σz is induced by the precession of carrier spins when currents flow through the cluster magnetic octupole, which also relies on the direction of the cluster magnetic octupole in conjunction with the applied current. With the aid of σz, current induced spin-orbit torque (SOT) switching of adjacent perpendicular ferromagnet is realized without external magnetic field. Our findings present a new perspective to the generation of out-of-plane spin polarizations via noncollinear AFM spin structure, and provide a potential path to realize ultrafast high-density applications.
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Affiliation(s)
- Yunfeng You
- Key Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China
| | - Hua Bai
- Key Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China
| | - Xiaoyu Feng
- The Key Lab for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou, 730000, China
| | - Xiaolong Fan
- The Key Lab for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou, 730000, China
| | - Lei Han
- Key Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China
| | - Xiaofeng Zhou
- Key Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China
| | - Yongjian Zhou
- Key Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China
| | - Ruiqi Zhang
- Key Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China
| | - Tongjin Chen
- Key Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China
| | - Feng Pan
- Key Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China
| | - Cheng Song
- Key Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China.
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40
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Prediction of unconventional magnetism in doped FeSb 2. Proc Natl Acad Sci U S A 2021; 118:2108924118. [PMID: 34649995 DOI: 10.1073/pnas.2108924118] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/02/2021] [Indexed: 11/18/2022] Open
Abstract
It is commonly believed that the energy bands of typical collinear antiferromagnets (AFs), which have zero net magnetization, are Kramers spin-degenerate. Kramers nondegeneracy is usually associated with a global time-reversal symmetry breaking (e.g., via ferromagnetism) or with a combination of spin-orbit interaction and broken spatial inversion symmetry. Recently, another type of spin splitting was demonstrated to emerge in some collinear magnets that are fully spin compensated by symmetry, nonrelativistic, and not even necessarily noncentrosymmetric. These materials feature nonzero spin density staggered in real space as seen in traditional AFs but also spin splitting in momentum space, generally seen only in ferromagnets. This results in a combination of materials characteristics typical of both ferromagnets and AFs. Here, we discuss this recently discovered class with application to a well-known semiconductor, FeSb2, and predict that with certain alloying, it becomes magnetic and metallic and features the aforementioned magnetic dualism. The calculated energy bands split antisymmetrically with respect to spin-degenerate nodal surfaces rather than nodal points, as in the case of spin-orbit splitting. The combination of a large (0.2-eV) spin splitting, compensated net magnetization with metallic ground state, and a specific magnetic easy axis generates a large anomalous Hall conductivity (∼150 S/cm) and a sizable magnetooptical Kerr effect, all deemed to be hallmarks of nonzero net magnetization. We identify a large contribution to the anomalous response originating from the spin-orbit interaction gapped anti-Kramers nodal surfaces, a mechanism distinct from the nodal lines and Weyl points in ferromagnets.
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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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Kimata M, Sasabe N, Kurita K, Yamasaki Y, Tabata C, Yokoyama Y, Kotani Y, Ikhlas M, Tomita T, Amemiya K, Nojiri H, Nakatsuji S, Koretsune T, Nakao H, Arima TH, Nakamura T. X-ray study of ferroic octupole order producing anomalous Hall effect. Nat Commun 2021; 12:5582. [PMID: 34552070 PMCID: PMC8458343 DOI: 10.1038/s41467-021-25834-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 08/29/2021] [Indexed: 11/21/2022] Open
Abstract
Recently found anomalous Hall, Nernst, magnetooptical Kerr, and spin Hall effects in the antiferromagnets Mn3X (X = Sn, Ge) are attracting much attention for spintronics and energy harvesting. Since these materials are antiferromagnets, the origin of these functionalities is expected to be different from that of conventional ferromagnets. Here, we report the observation of ferroic order of magnetic octupole in Mn3Sn by X-ray magnetic circular dichroism, which is only predicted theoretically so far. The observed signals are clearly decoupled with the behaviors of uniform magnetization, indicating that the present X-ray magnetic circular dichroism is not arising from the conventional magnetization. We have found that the appearance of this anomalous signal coincides with the time reversal symmetry broken cluster magnetic octupole order. Our study demonstrates that the exotic material functionalities are closely related to the multipole order, which can produce unconventional cross correlation functionalities.
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Affiliation(s)
- Motoi Kimata
- Institute for Materials Research, Tohoku University, Sendai, Miyagi, 980-8577, Japan.
| | - Norimasa Sasabe
- Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1 Kouto, Sayo, Hyogo, 679-5198, Japan
| | - Kensuke Kurita
- Department of Physics, Tohoku University, Sendai, Miyagi, 980-8578, Japan
| | - Yuichi Yamasaki
- Research and Services Division of Materials Data and Integrated System (MaDIS), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki, 305-0044, Japan
- Center for Emergent Matter Science (CEMS), RIKEN, Wako, 351-0198, Japan
- PRESTO, Japan Science and Technology Agency (JST), Tokyo, 102-0076, Japan
- Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki, 305-0801, Japan
| | - Chihiro Tabata
- Institute for Integrated Radiation and Nuclear Science, Kyoto University, Kumatori, Osaka, 590-0494, Japan
| | - Yuichi Yokoyama
- Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1 Kouto, Sayo, Hyogo, 679-5198, Japan
| | - Yoshinori Kotani
- Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1 Kouto, Sayo, Hyogo, 679-5198, Japan
| | - Muhammad Ikhlas
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - Takahiro Tomita
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - Kenta Amemiya
- Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki, 305-0801, Japan
| | - Hiroyuki Nojiri
- Institute for Materials Research, Tohoku University, Sendai, Miyagi, 980-8577, Japan
| | - Satoru Nakatsuji
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
- Department of Physics, University of Tokyo, Hongo, Tokyo, 113-0033, Japan
- The Institute for Quantum Matter, Johns Hopkins University, Baltimore, MD, 21218, USA
- Trans-scale Quantum Science Institute, University of Tokyo, Hongo, Tokyo, 113-8654, Japan
| | - Takashi Koretsune
- Department of Physics, Tohoku University, Sendai, Miyagi, 980-8578, Japan
| | - Hironori Nakao
- Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki, 305-0801, Japan
| | - Taka-Hisa Arima
- Center for Emergent Matter Science (CEMS), RIKEN, Wako, 351-0198, Japan
- Department of Advanced Materials Science, University of Tokyo, Kashiwa, 277-8561, Japan
| | - Tetsuya Nakamura
- Institute for Materials Research, Tohoku University, Sendai, Miyagi, 980-8577, Japan
- Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1 Kouto, Sayo, Hyogo, 679-5198, Japan
- International Center for Synchrotron Radiation Innovation Smart, Tohoku University, Sendai, Miyagi, 980-8577, Japan
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Luo X, Obeysekera D, Won C, Sung SH, Schnitzer N, Hovden R, Cheong SW, Yang J, Sun K, Zhao L. Ultrafast Modulations and Detection of a Ferro-Rotational Charge Density Wave Using Time-Resolved Electric Quadrupole Second Harmonic Generation. PHYSICAL REVIEW LETTERS 2021; 127:126401. [PMID: 34597104 DOI: 10.1103/physrevlett.127.126401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 06/04/2021] [Accepted: 08/06/2021] [Indexed: 06/13/2023]
Abstract
We show the ferro-rotational nature of the commensurate charge density wave (CCDW) in 1T-TaS_{2} and track its dynamic modulations by temperature-dependent and time-resolved electric quadrupole rotation anisotropy-second harmonic generation (EQ RA-SHG), respectively. The ultrafast modulations manifest as the breathing and the rotation of the EQ RA-SHG patterns at three frequencies around the reported single CCDW amplitude mode frequency. A sudden shift of the triplet frequencies and a dramatic increase in the breathing and rotation magnitude further reveal a photoinduced transient CDW phase across a critical pump fluence of ∼0.5 mJ/cm^{2}.
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Affiliation(s)
- Xiangpeng Luo
- Department of Physics, University of Michigan, 450 Church St, Ann Arbor, Michigan 48109, USA
| | - Dimuthu Obeysekera
- Department of Physics, New Jersey Institute of Technology, 323 Dr Martin Luther King Jr Blvd, Newark, New Jersey 07102, USA
| | - Choongjae Won
- Laboratory for Pohang Emergent Materials, Pohang Accelerator Laboratory and Max Plank POSTECH Center for Complex Phase Materials, Pohang University of Science and Technology, Pohang 790-784, Korea
| | - Suk Hyun Sung
- Department of Materials Sciences, University of Michigan, 2300 Hayward Street, Ann Arbor, Michigan 48109, USA
| | - Noah Schnitzer
- Department of Materials Sciences, University of Michigan, 2300 Hayward Street, Ann Arbor, Michigan 48109, USA
| | - Robert Hovden
- Department of Materials Sciences, University of Michigan, 2300 Hayward Street, Ann Arbor, Michigan 48109, USA
| | - Sang-Wook Cheong
- Laboratory for Pohang Emergent Materials, Pohang Accelerator Laboratory and Max Plank POSTECH Center for Complex Phase Materials, Pohang University of Science and Technology, Pohang 790-784, Korea
- Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Junjie Yang
- Department of Physics, New Jersey Institute of Technology, 323 Dr Martin Luther King Jr Blvd, Newark, New Jersey 07102, USA
| | - Kai Sun
- Department of Physics, University of Michigan, 450 Church St, Ann Arbor, Michigan 48109, USA
| | - Liuyan Zhao
- Department of Physics, University of Michigan, 450 Church St, Ann Arbor, Michigan 48109, USA
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44
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Zhao HC, Xia H, Hu S, Lv YY, Zhao ZR, He J, Liang E, Ni G, Chen LY, Qiu XP, Zhou SM, Zhao HB. Large ultrafast-modulated Voigt effect in noncollinear antiferromagnet Mn 3Sn. Nat Commun 2021; 12:5266. [PMID: 34489461 PMCID: PMC8421456 DOI: 10.1038/s41467-021-25654-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 08/18/2021] [Indexed: 11/15/2022] Open
Abstract
The time-resolved magneto-optical (MO) Voigt effect can be utilized to study the Néel order dynamics in antiferromagnetic (AFM) materials, but it has been limited for collinear AFM spin configuration. Here, we have demonstrated that in Mn3Sn with an inverse triangular spin structure, the quench of AFM order by ultrafast laser pulses can result in a large Voigt effect modulation. The modulated Voigt angle is significantly larger than the polarization rotation due to the crystal-structure related linear dichroism effect and the modulated MO Kerr angle arising from the ferroic ordering of cluster magnetic octupole. The AFM order quench time shows negligible change with increasing temperature approaching the Néel temperature (TN), in markedly contrast with the pronounced slowing-down demagnetization typically observed in conventional magnetic materials. This atypical behavior can be explained by the influence of weakened Dzyaloshinskii–Moriya interaction rather than the smaller exchange splitting on the diminished AFM order near TN. The temperature-insensitive ultrafast spin manipulation can pave the way for high-speed spintronic devices either working at a wide range of temperature or demanding spin switching near TN. Mn3Sn is an anti-ferromagnetic material which displays a large magneto-optical Kerr effect, despite lacking a ferromagnetic moment. Here, the authors show that likewise, Mn3Sn, also presents a particularly large magneto-optical Voigt signal, with a negligible change in the quench time over a wide temperature range.
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Affiliation(s)
- H C Zhao
- Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education), and Shanghai Ultra-precision Optical Manufacturing Engineering Research Center, Department of Optical Science and Engineering, Fudan University, Shanghai, China
| | - H Xia
- Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education), and Shanghai Ultra-precision Optical Manufacturing Engineering Research Center, Department of Optical Science and Engineering, Fudan University, Shanghai, China.,Department of Physics, Fudan University, Shanghai, China
| | - S Hu
- Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology and Pohl Institute of Solid State Physics and School of Physics Science and Engineering, Tongji University, Shanghai, China
| | - Y Y Lv
- Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology and Pohl Institute of Solid State Physics and School of Physics Science and Engineering, Tongji University, Shanghai, China
| | - Z R Zhao
- Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education), and Shanghai Ultra-precision Optical Manufacturing Engineering Research Center, Department of Optical Science and Engineering, Fudan University, Shanghai, China
| | - J He
- Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education), and Shanghai Ultra-precision Optical Manufacturing Engineering Research Center, Department of Optical Science and Engineering, Fudan University, Shanghai, China
| | - E Liang
- Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education), and Shanghai Ultra-precision Optical Manufacturing Engineering Research Center, Department of Optical Science and Engineering, Fudan University, Shanghai, China
| | - G Ni
- Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education), and Shanghai Ultra-precision Optical Manufacturing Engineering Research Center, Department of Optical Science and Engineering, Fudan University, Shanghai, China.
| | - L Y Chen
- Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education), and Shanghai Ultra-precision Optical Manufacturing Engineering Research Center, Department of Optical Science and Engineering, Fudan University, Shanghai, China
| | - X P Qiu
- Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology and Pohl Institute of Solid State Physics and School of Physics Science and Engineering, Tongji University, Shanghai, China.
| | - S M Zhou
- Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology and Pohl Institute of Solid State Physics and School of Physics Science and Engineering, Tongji University, Shanghai, China.
| | - H B Zhao
- Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education), and Shanghai Ultra-precision Optical Manufacturing Engineering Research Center, Department of Optical Science and Engineering, Fudan University, Shanghai, China. .,Shanghai Frontier Base of Intelligent Optoelectronics and Perception, Institute of Optoelectronics, Fudan University, Shanghai, China.
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45
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Zhang J, Lee WK, Tu R, Rhee D, Zhao R, Wang X, Liu X, Hu X, Zhang X, Odom TW, Yan M. Spontaneous Formation of Ordered Magnetic Domains by Patterning Stress. NANO LETTERS 2021; 21:5430-5437. [PMID: 33847117 DOI: 10.1021/acs.nanolett.1c00070] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The formation of ordered magnetic domains in thin films is important for the magnetic microdevices in spin-electronics, magneto-optics, and magnetic microelectromechanical systems. Although inducing anisotropic stress in magnetostrictive materials can achieve the domain assembly, controlling magnetic anisotropy over microscale areas is challenging. In this work, we realized the microscopic patterning of magnetic domains by engineering stress distribution. Deposition of ferromagnetic thin films on nanotrenched polymeric layers induced tensile stress at the interfaces, giving rise to the directional magnetoelastic coupling to form ordered domains spontaneously. By changing the periodicity and shape of nanotrenches, we spatially tuned the geometric configuration of domains by design. Theoretical analysis and micromagnetic characterization confirmed that the local stress distribution by the topographic confinement dominates the forming mechanism of the directed magnetization.
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Affiliation(s)
- Jian Zhang
- Institute of Advanced Magnetic Materials, Hangzhou Dianzi University, Hangzhou, 310018, PR China
| | - Won-Kyu Lee
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
- Department of Materials Science and Engineering, Hongik University, Seoul 04066, Korea
| | - Rui Tu
- Institute of Advanced Magnetic Materials, Hangzhou Dianzi University, Hangzhou, 310018, PR China
| | - Dongjoon Rhee
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - Rongzhi Zhao
- Institute of Advanced Magnetic Materials, Hangzhou Dianzi University, Hangzhou, 310018, PR China
| | - Xinyu Wang
- Institute of Advanced Magnetic Materials, Hangzhou Dianzi University, Hangzhou, 310018, PR China
| | - Xiaolian Liu
- Institute of Advanced Magnetic Materials, Hangzhou Dianzi University, Hangzhou, 310018, PR China
| | - Xin Hu
- Institute of Advanced Magnetic Materials, Hangzhou Dianzi University, Hangzhou, 310018, PR China
| | - Xuefeng Zhang
- Institute of Advanced Magnetic Materials, Hangzhou Dianzi University, Hangzhou, 310018, PR China
| | - Teri W Odom
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Mi Yan
- Institute of Advanced Magnetic Materials, Hangzhou Dianzi University, Hangzhou, 310018, PR China
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46
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Li X, Zhu Z, Behnia K. A Monomaterial Nernst Thermopile with Hermaphroditic Legs. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2100751. [PMID: 33844874 DOI: 10.1002/adma.202100751] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 02/24/2021] [Indexed: 06/12/2023]
Abstract
A large transverse thermoelectric response, known as the anomalous Nernst effect (ANE) has been recently observed in several topological magnets. Building a thermopile employing this effect has been the subject of several recent propositions. Here, a thermopile is designed and built with an array of tilted adjacent crystals of Mn3 Sn. The design employs a single material and replaces pairs of P and N thermocouples of the traditional design with hermaphroditic legs. The design exploits the large lag angle between the applied field and the magnetization, which is attributed to the interruption of magnetic octupoles at the edge of the xy-plane. Eliminating extrinsic contact between the legs will boost the efficiency, simplify the process, and pave the way for a new generation of thermopiles.
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Affiliation(s)
- Xiaokang Li
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Zengwei Zhu
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Kamran Behnia
- Laboratoire de Physique et d'Etude des Matériaux (CNRS-Sorbonne Université), ESPCI, PSL Research University, Paris, 75005, France
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47
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Miwa S, Iihama S, Nomoto T, Tomita T, Higo T, Ikhlas M, Sakamoto S, Otani Y, Mizukami S, Arita R, Nakatsuji S. Giant Effective Damping of Octupole Oscillation in an Antiferromagnetic Weyl Semimetal. SMALL SCIENCE 2021. [DOI: 10.1002/smsc.202000062] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- Shinji Miwa
- The Institute for Solid State Physics The University of Tokyo Kashiwa Chiba 277-8581 Japan
- Trans-scale Quantum Science Institute The University of Tokyo Bunkyo Tokyo 113-0033 Japan
- CREST Japan Science and Technology Agency (JST) Kawaguchi Saitama 332-0012 Japan
| | - Satoshi Iihama
- CREST Japan Science and Technology Agency (JST) Kawaguchi Saitama 332-0012 Japan
- Frontier Research Institute for Interdisciplinary Sciences (FRIS) Tohoku University Sendai Miyagi 980-8578 Japan
- Advanced Institute for Materials Research (AIMR) Tohoku University Sendai Miyagi 980-8577 Japan
- Center for Spintronics Research Network (CSRN) Tohoku University Sendai Miyagi 980-8577 Japan
| | - Takuya Nomoto
- CREST Japan Science and Technology Agency (JST) Kawaguchi Saitama 332-0012 Japan
- Department of Applied Physics The University of Tokyo Tokyo 113-8656 Japan
| | - Takahiro Tomita
- The Institute for Solid State Physics The University of Tokyo Kashiwa Chiba 277-8581 Japan
- CREST Japan Science and Technology Agency (JST) Kawaguchi Saitama 332-0012 Japan
| | - Tomoya Higo
- CREST Japan Science and Technology Agency (JST) Kawaguchi Saitama 332-0012 Japan
- Department of Physics The University of Tokyo Tokyo 113-0033 Japan
| | - Muhammad Ikhlas
- The Institute for Solid State Physics The University of Tokyo Kashiwa Chiba 277-8581 Japan
| | - Shoya Sakamoto
- The Institute for Solid State Physics The University of Tokyo Kashiwa Chiba 277-8581 Japan
| | - YoshiChika Otani
- The Institute for Solid State Physics The University of Tokyo Kashiwa Chiba 277-8581 Japan
- Trans-scale Quantum Science Institute The University of Tokyo Bunkyo Tokyo 113-0033 Japan
- CREST Japan Science and Technology Agency (JST) Kawaguchi Saitama 332-0012 Japan
- RIKEN, Center for Emergent Matter Science (CEMS) Wako Saitama 351-0198 Japan
| | - Shigemi Mizukami
- Advanced Institute for Materials Research (AIMR) Tohoku University Sendai Miyagi 980-8577 Japan
- Center for Spintronics Research Network (CSRN) Tohoku University Sendai Miyagi 980-8577 Japan
- Center for Science and Innovation in Spintronics (CSIS) Tohoku University Sendai Miyagi 980-8577 Japan
| | - Ryotaro Arita
- CREST Japan Science and Technology Agency (JST) Kawaguchi Saitama 332-0012 Japan
- Department of Applied Physics The University of Tokyo Tokyo 113-8656 Japan
- RIKEN, Center for Emergent Matter Science (CEMS) Wako Saitama 351-0198 Japan
| | - Satoru Nakatsuji
- The Institute for Solid State Physics The University of Tokyo Kashiwa Chiba 277-8581 Japan
- Trans-scale Quantum Science Institute The University of Tokyo Bunkyo Tokyo 113-0033 Japan
- CREST Japan Science and Technology Agency (JST) Kawaguchi Saitama 332-0012 Japan
- Department of Physics The University of Tokyo Tokyo 113-0033 Japan
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48
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Tsai H, Higo T, Kondou K, Sakamoto S, Kobayashi A, Matsuo T, Miwa S, Otani Y, Nakatsuji S. Large Hall Signal due to Electrical Switching of an Antiferromagnetic Weyl Semimetal State. SMALL SCIENCE 2021. [DOI: 10.1002/smsc.202000025] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Hanshen Tsai
- Institute for Solid State Physics University of Tokyo Kashiwa Chiba 277-8581 Japan
- CREST Japan Science and Technology Agency Kawaguchi Saitama 332-0012 Japan
| | - Tomoya Higo
- Institute for Solid State Physics University of Tokyo Kashiwa Chiba 277-8581 Japan
- CREST Japan Science and Technology Agency Kawaguchi Saitama 332-0012 Japan
| | - Kouta Kondou
- Institute for Solid State Physics University of Tokyo Kashiwa Chiba 277-8581 Japan
- CREST Japan Science and Technology Agency Kawaguchi Saitama 332-0012 Japan
- RIKEN Center for Emergent Matter Science (CEMS) Wako Saitama 351-0198 Japan
| | - Shoya Sakamoto
- Institute for Solid State Physics University of Tokyo Kashiwa Chiba 277-8581 Japan
| | - Ayuko Kobayashi
- Institute for Solid State Physics University of Tokyo Kashiwa Chiba 277-8581 Japan
| | - Takumi Matsuo
- Institute for Solid State Physics University of Tokyo Kashiwa Chiba 277-8581 Japan
| | - Shinji Miwa
- Institute for Solid State Physics University of Tokyo Kashiwa Chiba 277-8581 Japan
- CREST Japan Science and Technology Agency Kawaguchi Saitama 332-0012 Japan
- Trans-scale Quantum Science Institute University of Tokyo Bunkyo-ku Tokyo 113-0033 Japan
| | - Yoshichika Otani
- Institute for Solid State Physics University of Tokyo Kashiwa Chiba 277-8581 Japan
- CREST Japan Science and Technology Agency Kawaguchi Saitama 332-0012 Japan
- RIKEN Center for Emergent Matter Science (CEMS) Wako Saitama 351-0198 Japan
- Trans-scale Quantum Science Institute University of Tokyo Bunkyo-ku Tokyo 113-0033 Japan
| | - Satoru Nakatsuji
- Institute for Solid State Physics University of Tokyo Kashiwa Chiba 277-8581 Japan
- CREST Japan Science and Technology Agency Kawaguchi Saitama 332-0012 Japan
- Trans-scale Quantum Science Institute University of Tokyo Bunkyo-ku Tokyo 113-0033 Japan
- Department of Physics University of Tokyo Bunkyo-ku Tokyo 113-0033 Japan
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49
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Cheng B, Schumann T, Stemmer S, Armitage NP. Probing charge pumping and relaxation of the chiral anomaly in a Dirac semimetal. SCIENCE ADVANCES 2021; 7:eabg0914. [PMID: 33863734 PMCID: PMC8051870 DOI: 10.1126/sciadv.abg0914] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 03/01/2021] [Indexed: 06/12/2023]
Abstract
The linear band crossings of 3D Dirac and Weyl semimetals are characterized by a charge chirality, the parallel or antiparallel locking of electron spin to its momentum. These materials are believed to exhibit an E · B chiral magnetic effect that is associated with the near conservation of chiral charge. Here, we use magneto-terahertz spectroscopy to study epitaxial Cd3As2 films and extract their conductivities σ(ω) as a function of E · B. As field is applied, we observe a markedly sharp Drude response that rises out of the broader background. Its appearance is a definitive signature of a new transport channel and consistent with the chiral response, with its spectral weight a measure of the net chiral charge and width a measure of the scattering rate between chiral species. The field independence of the chiral relaxation establishes that it is set by the approximate conservation of the isospin that labels the crystalline point-group representations.
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Affiliation(s)
- Bing Cheng
- Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Timo Schumann
- Materials Department, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Susanne Stemmer
- Materials Department, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - N P Armitage
- Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA.
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50
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Kumar N, Guin SN, Manna K, Shekhar C, Felser C. Topological Quantum Materials from the Viewpoint of Chemistry. Chem Rev 2021; 121:2780-2815. [PMID: 33151662 PMCID: PMC7953380 DOI: 10.1021/acs.chemrev.0c00732] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Indexed: 11/29/2022]
Abstract
Topology, a mathematical concept, has recently become a popular and truly transdisciplinary topic encompassing condensed matter physics, solid state chemistry, and materials science. Since there is a direct connection between real space, namely atoms, valence electrons, bonds, and orbitals, and reciprocal space, namely bands and Fermi surfaces, via symmetry and topology, classifying topological materials within a single-particle picture is possible. Currently, most materials are classified as trivial insulators, semimetals, and metals or as topological insulators, Dirac and Weyl nodal-line semimetals, and topological metals. The key ingredients for topology are certain symmetries, the inert pair effect of the outer electrons leading to inversion of the conduction and valence bands, and spin-orbit coupling. This review presents the topological concepts related to solids from the viewpoint of a solid-state chemist, summarizes techniques for growing single crystals, and describes basic physical property measurement techniques to characterize topological materials beyond their structure and provide examples of such materials. Finally, a brief outlook on the impact of topology in other areas of chemistry is provided at the end of the article.
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Affiliation(s)
- Nitesh Kumar
- Max Planck Institute for
Chemical
Physics of Solids, 01187 Dresden, Germany
| | - Satya N. Guin
- Max Planck Institute for
Chemical
Physics of Solids, 01187 Dresden, Germany
| | - Kaustuv Manna
- Max Planck Institute for
Chemical
Physics of Solids, 01187 Dresden, Germany
| | - Chandra Shekhar
- Max Planck Institute for
Chemical
Physics of Solids, 01187 Dresden, Germany
| | - Claudia Felser
- Max Planck Institute for
Chemical
Physics of Solids, 01187 Dresden, Germany
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