1
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He Z, Li Z, Chen Z, Wang Z, Shen J, Wang S, Song C, Zhao T, Cai J, Lin SZ, Zhang Y, Shen B. Experimental observation of current-driven antiskyrmion sliding in stripe domains. NATURE MATERIALS 2024; 23:1048-1054. [PMID: 38605194 DOI: 10.1038/s41563-024-01870-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Accepted: 03/18/2024] [Indexed: 04/13/2024]
Abstract
Magnetic skyrmions are promising as next-generation information units. Their antiparticle-the antiskyrmion-has also been discovered in chiral magnets. Here we experimentally demonstrate antiskyrmion sliding in response to a pulsed electric current at room temperature without the requirement of an external magnetic field. This is realized by embedding antiskyrmions in helical stripe domains, which naturally provide one-dimensional straight tracks along which antiskyrmion sliding can be easily launched with low current density and without transverse deflection from the antiskyrmion Hall effect. The higher mobility of the antiskyrmions in the background of helical stripes in contrast to the typical ferromagnetic state is a result of intrinsic material parameters and elastic energy of the stripe domain, thereby smearing out the random pinning potential, as supported by micromagnetic simulations. The demonstration and comprehensive understanding of antiskyrmion movement along naturally straight tracks offers a new perspective for (anti)skyrmion application in spintronics.
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Affiliation(s)
- Zhidong He
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Zhuolin Li
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Zhaohui Chen
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing, China
| | - Zhan Wang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - Jun Shen
- Department of Energy and Power Engineering, School of Mechanical Engineering, Beijing Institute of Technology, Beijing, China
| | - Shouguo Wang
- Anhui Key Laboratory of Magnetic Functional Materials and Devices, School of Materials Science and Engineering, Anhui University, Hefei, China
| | - Cheng Song
- Key Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing, China
| | - Tongyun Zhao
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Jianwang Cai
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Shi-Zeng Lin
- Theoretical Division and Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM, USA.
| | - Ying Zhang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China.
- Songshan Lake Materials Laboratory, Dongguan, China.
| | - Baogen Shen
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
- Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences, Ningbo, China
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2
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Song D, Wang W, Zhang S, Liu Y, Wang N, Zheng F, Tian M, Dunin-Borkowski RE, Zang J, Du H. Steady motion of 80-nm-size skyrmions in a 100-nm-wide track. Nat Commun 2024; 15:5614. [PMID: 38965221 PMCID: PMC11224351 DOI: 10.1038/s41467-024-49976-6] [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: 03/21/2024] [Accepted: 06/27/2024] [Indexed: 07/06/2024] Open
Abstract
The current-driven movement of magnetic skyrmions along a nanostripe is essential for the advancement and functionality of a new category of spintronic devices resembling racetracks. Despite extensive research into skyrmion dynamics, experimental verification of current-induced motion of ultra-small skyrmions within an ultrathin nanostripe is still pending. Here, we unveil the motion of individual 80 nm-size skyrmions in an FeGe track with an ultrathin width of 100 nm. The skyrmions can move steadily along the track over a broad range of current densities by using controlled pulse durations of as low as 2 ns. The potential landscape, arising from the magnetic edge twists in such a geometrically confined system, introduces skyrmion inertia and ensures efficient motion with a vanishing skyrmion Hall angle. Our results showcase the steady motion of skyrmions in an ultrathin track, offering a practical pathway for implementing skyrmion-based spintronic devices.
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Affiliation(s)
- Dongsheng Song
- Institutes of Physical Science and Information Technology, Anhui University, Hefei, 230601, China.
- Anhui Province Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei, Anhui, 230031, China.
| | - Weiwei Wang
- Institutes of Physical Science and Information Technology, Anhui University, Hefei, 230601, China
- Anhui Province Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei, Anhui, 230031, China
| | - Shuisen Zhang
- Anhui Province Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei, Anhui, 230031, China
- University of Science and Technology of China, Hefei, 230026, China
| | - Yizhou Liu
- Anhui Province Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei, Anhui, 230031, China
| | - Ning Wang
- Anhui Province Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei, Anhui, 230031, China
| | - Fengshan Zheng
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich, 52425, Jülich, Germany
- Spin-X Institute, Center for Electron Microscopy, School of Physics and Optoelectronics State Key Laboratory of Luminescent Materials and Devices Guangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional Materials, South China University of Technology, Guangzhou, 511442, P. R. China
| | - Mingliang Tian
- Anhui Province Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei, Anhui, 230031, China
- Science Island Branch of Graduate School, University of Science and Technology of China, Hefei, Anhui, 230026, China
- School of Physics and Optoelectronic Engineering, Anhui University, Hefei, 230601, China
| | - Rafal E Dunin-Borkowski
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Jiadong Zang
- Department of Physics and Astronomy, University of New Hampshire, Durham, NH, 03824, USA
- Materials Science Program, University of New Hampshire, Durham, NH, 03824, USA
| | - Haifeng Du
- Institutes of Physical Science and Information Technology, Anhui University, Hefei, 230601, China.
- Anhui Province Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei, Anhui, 230031, China.
- Science Island Branch of Graduate School, University of Science and Technology of China, Hefei, Anhui, 230026, China.
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3
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Wang Y, Xing J, Zhao Y, Wang Y, Zhao J, Jiang X. Alloying Driven Antiferromagnetic Skyrmions on NiPS 3 Monolayer: A First-Principles Calculation. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2401048. [PMID: 38647400 PMCID: PMC11220710 DOI: 10.1002/advs.202401048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2024] [Revised: 03/25/2024] [Indexed: 04/25/2024]
Abstract
Topological magnetic states are promising information carriers for ultrahigh-density and high-efficiency magnetic storage. Recent advances in two-dimensional (2D) magnets provide powerful platforms for stabilizing various nanometer-size topological spin textures within a wide range of magnetic field and temperature. However, non-centrosymmetric 2D magnets with broken inversion symmetry are scarce in nature, making direct observations of the chiral spin structure difficult, especially for antiferromagnetic (AFM) skyrmions. In this work, it is theoretically predicted that intrinsic AFM skyrmions can be easily triggered in XY-type honeycomb magnet NiPS3 monolayer by alloying of Cr atoms, due to the presence of a sizable Dzyaloshinskii-Moriya interaction. More interestingly, the diameter of the AFM skyrmions in Ni3/4Cr1/4PS3 decreases from 12 to 4.4 nm as the external magnetic field increases and the skyrmion phases remain stable up to an external magnetic field of 4 T. These results highlight an effective strategy to generate and modulate the topological spin texture in 2D magnets by alloying with magnetic element.
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Affiliation(s)
- Yanxia Wang
- Key Laboratory of Materials Modification by LaserIon and Electron BeamsDalian University of TechnologyMinistry of EducationDalian116024China
| | - Jianpei Xing
- Key Laboratory of Materials Modification by LaserIon and Electron BeamsDalian University of TechnologyMinistry of EducationDalian116024China
| | - Ying Zhao
- Key Laboratory of Materials Modification by LaserIon and Electron BeamsDalian University of TechnologyMinistry of EducationDalian116024China
| | - Yi Wang
- Key Laboratory of Materials Modification by LaserIon and Electron BeamsDalian University of TechnologyMinistry of EducationDalian116024China
| | - Jijun Zhao
- Key Laboratory of Materials Modification by LaserIon and Electron BeamsDalian University of TechnologyMinistry of EducationDalian116024China
- Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum MaterialsSchool of PhysicsSouth China Normal UniversityGuangzhou510006China
- Guangdong‐Hong Kong Joint Laboratory of Quantum MatterFrontier Research Institute for PhysicsSouth China Normal UniversityGuangzhou510006China
| | - Xue Jiang
- Key Laboratory of Materials Modification by LaserIon and Electron BeamsDalian University of TechnologyMinistry of EducationDalian116024China
- Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum MaterialsSchool of PhysicsSouth China Normal UniversityGuangzhou510006China
- Guangdong‐Hong Kong Joint Laboratory of Quantum MatterFrontier Research Institute for PhysicsSouth China Normal UniversityGuangzhou510006China
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4
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Zhou Y, Li S, Liang X, Zhou Y. Topological Spin Textures: Basic Physics and Devices. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2312935. [PMID: 38861696 DOI: 10.1002/adma.202312935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 05/24/2024] [Indexed: 06/13/2024]
Abstract
In the face of escalating modern data storage demands and the constraints of Moore's Law, exploring spintronic solutions, particularly the devices based on magnetic skyrmions, has emerged as a promising frontier in scientific research. Since the first experimental observation of skyrmions, topological spin textures have been extensively studied for their great potential as efficient information carriers in spintronic devices. However, significant challenges have emerged alongside this progress. This review aims to synthesize recent advances in skyrmion research while addressing the major issues encountered in the field. Additionally, current research on promising topological spin structures in addition to skyrmions is summarized. Beyond 2D structures, exploration also extends to 1D magnetic solitons and 3D spin textures. In addition, a diverse array of emerging magnetic materials is introduced, including antiferromagnets and 2D van der Waals magnets, broadening the scope of potential materials hosting topological spin textures. Through a systematic examination of magnetic principles, topological categorization, and the dynamics of spin textures, a comprehensive overview of experimental and theoretical advances in the research of topological magnetism is provided. Finally, both conventional and unconventional applications are summarized based on spin textures proposed thus far. This review provides an outlook on future development in applied spintronics.
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Affiliation(s)
- Yuqing Zhou
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong, 518172, China
| | - Shuang Li
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong, 518172, China
| | - Xue Liang
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong, 518172, China
| | - Yan Zhou
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong, 518172, China
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5
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Lee Y, Kim C, Son S, Cui J, Park G, Zhang KX, Oh S, Cheong H, Kleibert A, Park JG. Imaging Thermally Fluctuating Néel Vectors in van der Waals Antiferromagnet NiPS 3. NANO LETTERS 2024; 24:6043-6050. [PMID: 38717152 DOI: 10.1021/acs.nanolett.4c00804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2024]
Abstract
Studying antiferromagnetic domains is essential for fundamental physics and potential spintronics applications. Despite their importance, few systematic studies have been performed on antiferromagnet (AFM) domains with high spatial resolution in van der Waals (vdW) materials, and direct probing of the Néel vectors remains challenging. In this work, we found multidomain states in the vdW AFM NiPS3, a material extensively investigated for its unique magnetic exciton. We employed photoemission electron microscopy combined with the X-ray magnetic linear dichroism (XMLD-PEEM) to image the NiPS3's magnetic structure. The nanometer-spatial resolution of XMLD-PEEM allows us to determine local Néel vector orientations and discover thermally fluctuating Néel vectors that are independent of the crystal symmetry even at 65 K, well below the TN of 155 K. We demonstrate that an in-plane orbital moment of the Ni ion is responsible for the weak magnetocrystalline anisotropy. The observed thermal fluctuations of the antiferromagnetic domains may explain the broadening of magnetic exciton peaks at higher temperatures.
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Affiliation(s)
- Youjin Lee
- Center for Quantum Materials, Seoul National University, Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy & Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Chaebin Kim
- Center for Quantum Materials, Seoul National University, Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy & Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Suhan Son
- Center for Quantum Materials, Seoul National University, Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy & Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jingyuan Cui
- Center for Quantum Materials, Seoul National University, Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy & Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Giung Park
- Center for Quantum Materials, Seoul National University, Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy & Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Kai-Xuan Zhang
- Center for Quantum Materials, Seoul National University, Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy & Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Siwon Oh
- Department of Physics, Sogang University, Seoul, 04107, Republic of Korea
| | - Hyeonsik Cheong
- Department of Physics, Sogang University, Seoul, 04107, Republic of Korea
| | - Armin Kleibert
- Swiss Light Source, Paul Scherrer Institut, Villigen, PSI CH-5232, Switzerland
| | - Je-Geun Park
- Center for Quantum Materials, Seoul National University, Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy & Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea
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6
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Cui Q, Zhu Y, Jiang J, Cui P, Yang H, Chang K, Wang K. Anatomy of Hidden Dzyaloshinskii-Moriya Interactions and Topological Spin Textures in Centrosymmetric Crystals. NANO LETTERS 2024. [PMID: 38739551 DOI: 10.1021/acs.nanolett.4c01486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
The Dzyaloshinskii-Moriya interaction (DMI) is understood to be forbidden by the symmetry of centrosymmetric systems, thus restricting the candidate types for investigating many correlated physical phenomena. Here, we report the hidden DMI existing in centrosymmetric magnets driven by the local inversion symmetry breaking of specific spin sublattices. The opposite DMI spatially localized on the inverse spin sublattice favors the separated spin spiral with opposite chirality. Furthermore, we elucidate that hidden DMI widely exists in many potential candidates, from the first-principles calculations on the mature crystal database. Interestingly, novel topological spin configurations, such as the anti-chirality-locked merons and antiferromagnetic-ferromagnetic meron chains, are stabilized as a consequence of hidden DMI. Our understanding enables the effective control of DMI by symmetry operations at the atomic level and enlarges the range of currently useful magnets for topological magnetism.
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Affiliation(s)
- Qirui Cui
- Center for Quantum Matter, School of Physics, Zhejiang University, Hangzhou 310027, Zhejiang, China
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
| | - Yingmei Zhu
- Key Laboratory of Spintronics Materials, Devices and Systems of Zhejiang Province, Hangzhou 311305, China
| | - Jiawei Jiang
- Center for Quantum Matter, School of Physics, Zhejiang University, Hangzhou 310027, Zhejiang, China
| | - Ping Cui
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
- Yongjiang Laboratory, Ningbo 315202, China
| | - Hongxin Yang
- Center for Quantum Matter, School of Physics, Zhejiang University, Hangzhou 310027, Zhejiang, China
| | - Kai Chang
- Center for Quantum Matter, School of Physics, Zhejiang University, Hangzhou 310027, Zhejiang, China
| | - Kaiyou Wang
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
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7
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Jani H, Harrison J, Hooda S, Prakash S, Nandi P, Hu J, Zeng Z, Lin JC, Godfrey C, Omar GJ, Butcher TA, Raabe J, Finizio S, Thean AVY, Ariando A, Radaelli PG. Spatially reconfigurable antiferromagnetic states in topologically rich free-standing nanomembranes. NATURE MATERIALS 2024; 23:619-626. [PMID: 38374414 PMCID: PMC11068574 DOI: 10.1038/s41563-024-01806-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Accepted: 01/11/2024] [Indexed: 02/21/2024]
Abstract
Antiferromagnets hosting real-space topological textures are promising platforms to model fundamental ultrafast phenomena and explore spintronics. However, they have only been epitaxially fabricated on specific symmetry-matched substrates, thereby preserving their intrinsic magneto-crystalline order. This curtails their integration with dissimilar supports, restricting the scope of fundamental and applied investigations. Here we circumvent this limitation by designing detachable crystalline antiferromagnetic nanomembranes of α-Fe2O3. First, we show-via transmission-based antiferromagnetic vector mapping-that flat nanomembranes host a spin-reorientation transition and rich topological phenomenology. Second, we exploit their extreme flexibility to demonstrate the reconfiguration of antiferromagnetic states across three-dimensional membrane folds resulting from flexure-induced strains. Finally, we combine these developments using a controlled manipulator to realize the strain-driven non-thermal generation of topological textures at room temperature. The integration of such free-standing antiferromagnetic layers with flat/curved nanostructures could enable spin texture designs via magnetoelastic/geometric effects in the quasi-static and dynamical regimes, opening new explorations into curvilinear antiferromagnetism and unconventional computing.
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Affiliation(s)
- Hariom Jani
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK.
- Department of Physics, National University of Singapore, Singapore, Singapore.
| | - Jack Harrison
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK
| | - Sonu Hooda
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore
| | - Saurav Prakash
- Department of Physics, National University of Singapore, Singapore, Singapore
| | - Proloy Nandi
- Department of Physics, National University of Singapore, Singapore, Singapore
| | - Junxiong Hu
- Department of Physics, National University of Singapore, Singapore, Singapore.
| | - Zhiyang Zeng
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK
| | - Jheng-Cyuan Lin
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK
| | - Charles Godfrey
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK
| | - Ganesh Ji Omar
- Department of Physics, National University of Singapore, Singapore, Singapore
| | - Tim A Butcher
- Swiss Light Source, Paul Scherrer Institut, Villigen, Switzerland
| | - Jörg Raabe
- Swiss Light Source, Paul Scherrer Institut, Villigen, Switzerland
| | - Simone Finizio
- Swiss Light Source, Paul Scherrer Institut, Villigen, Switzerland.
| | - Aaron Voon-Yew Thean
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore
- Integrative Sciences and Engineering Programme, National University of Singapore, Singapore, Singapore
| | - A Ariando
- Department of Physics, National University of Singapore, Singapore, Singapore.
- Integrative Sciences and Engineering Programme, National University of Singapore, Singapore, Singapore.
| | - Paolo G Radaelli
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK.
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8
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Pham VT, Sisodia N, Di Manici I, Urrestarazu-Larrañaga J, Bairagi K, Pelloux-Prayer J, Guedas R, Buda-Prejbeanu LD, Auffret S, Locatelli A, Menteş TO, Pizzini S, Kumar P, Finco A, Jacques V, Gaudin G, Boulle O. Fast current-induced skyrmion motion in synthetic antiferromagnets. Science 2024; 384:307-312. [PMID: 38635712 DOI: 10.1126/science.add5751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 03/14/2024] [Indexed: 04/20/2024]
Abstract
Magnetic skyrmions are topological magnetic textures that hold great promise as nanoscale bits of information in memory and logic devices. Although room-temperature ferromagnetic skyrmions and their current-induced manipulation have been demonstrated, their velocity has been limited to about 100 meters per second. In addition, their dynamics are perturbed by the skyrmion Hall effect, a motion transverse to the current direction caused by the skyrmion topological charge. Here, we show that skyrmions in compensated synthetic antiferromagnets can be moved by current along the current direction at velocities of up to 900 meters per second. This can be explained by the cancellation of the net topological charge leading to a vanishing skyrmion Hall effect. Our results open an important path toward the realization of logic and memory devices based on the fast manipulation of skyrmions in tracks.
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Affiliation(s)
- Van Tuong Pham
- Université Grenoble Alpes, CNRS, CEA, SPINTEC, 38054 Grenoble, France
- Université Grenoble Alpes, CNRS, Institut Néel, 38042 Grenoble, France
| | - Naveen Sisodia
- Université Grenoble Alpes, CNRS, CEA, SPINTEC, 38054 Grenoble, France
- Department of Physics, Indian Institute of Technology Gandhinagar, Gandhinagar 382355, Gujarat, India
| | - Ilaria Di Manici
- Université Grenoble Alpes, CNRS, CEA, SPINTEC, 38054 Grenoble, France
| | | | - Kaushik Bairagi
- Université Grenoble Alpes, CNRS, CEA, SPINTEC, 38054 Grenoble, France
| | | | - Rodrigo Guedas
- Université Grenoble Alpes, CNRS, CEA, SPINTEC, 38054 Grenoble, France
- Instituto de Sistemas Optoelectrónicos y Microtecnología (ISOM), Universidad Politécnica de Madrid, 28040 Madrid, Spain
| | | | - Stéphane Auffret
- Université Grenoble Alpes, CNRS, CEA, SPINTEC, 38054 Grenoble, France
| | - Andrea Locatelli
- Elettra-Sincrotrone Trieste S.C.p.A., 34149 Basovizza, Trieste, Italy
| | | | - Stefania Pizzini
- Université Grenoble Alpes, CNRS, Institut Néel, 38042 Grenoble, France
| | - Pawan Kumar
- Laboratoire Charles Coulomb, Université de Montpellier, CNRS, 34095 Montpellier, France
| | - Aurore Finco
- Laboratoire Charles Coulomb, Université de Montpellier, CNRS, 34095 Montpellier, France
| | - Vincent Jacques
- Laboratoire Charles Coulomb, Université de Montpellier, CNRS, 34095 Montpellier, France
| | - Gilles Gaudin
- Université Grenoble Alpes, CNRS, CEA, SPINTEC, 38054 Grenoble, France
| | - Olivier Boulle
- Université Grenoble Alpes, CNRS, CEA, SPINTEC, 38054 Grenoble, France
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9
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Bhukta M, Dohi T, Bharadwaj VK, Zarzuela R, Syskaki MA, Foerster M, Niño MA, Sinova J, Frömter R, Kläui M. Homochiral antiferromagnetic merons, antimerons and bimerons realized in synthetic antiferromagnets. Nat Commun 2024; 15:1641. [PMID: 38409221 PMCID: PMC10897388 DOI: 10.1038/s41467-024-45375-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 01/23/2024] [Indexed: 02/28/2024] Open
Abstract
The ever-growing demand for device miniaturization and energy efficiency in data storage and computing technology has prompted a shift towards antiferromagnetic topological spin textures as information carriers. This shift is primarily owing to their negligible stray fields, leading to higher possible device density and potentially ultrafast dynamics. We realize in this work such chiral in-plane topological antiferromagnetic spin textures namely merons, antimerons, and bimerons in synthetic antiferromagnets by concurrently engineering the effective perpendicular magnetic anisotropy, the interlayer exchange coupling, and the magnetic compensation ratio. We demonstrate multimodal vector imaging of the three-dimensional Néel order parameter, revealing the topology of those spin textures and a globally well-defined chirality, which is a crucial requirement for controlled current-induced dynamics. Our analysis reveals that the interplay between interlayer exchange and interlayer magnetic dipolar interactions plays a key role to significantly reduce the critical strength of the Dzyaloshinskii-Moriya interaction required to stabilize topological spin textures, such as antiferromagnetic merons, in synthetic antiferromagnets, making them a promising platform for next-generation spintronics applications.
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Affiliation(s)
- Mona Bhukta
- Institute of Physics, Johannes Gutenberg-University Mainz, 55099, Mainz, Germany
| | - Takaaki Dohi
- Institute of Physics, Johannes Gutenberg-University Mainz, 55099, Mainz, Germany.
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba, Sendai, 980-8577, Japan.
| | | | - Ricardo Zarzuela
- Institute of Physics, Johannes Gutenberg-University Mainz, 55099, Mainz, Germany
| | - Maria-Andromachi Syskaki
- Institute of Physics, Johannes Gutenberg-University Mainz, 55099, Mainz, Germany
- Singulus Technologies AG, Hanauer Landstrasse 107, 63796, Kahl am Main, Germany
| | - Michael Foerster
- ALBA Synchrotron Light Facility, 08290, Cerdanyola del Vallés, Barcelona, Spain
| | - Miguel Angel Niño
- ALBA Synchrotron Light Facility, 08290, Cerdanyola del Vallés, Barcelona, Spain
| | - Jairo Sinova
- Institute of Physics, Johannes Gutenberg-University Mainz, 55099, Mainz, Germany
| | - Robert Frömter
- Institute of Physics, Johannes Gutenberg-University Mainz, 55099, Mainz, Germany.
| | - Mathias Kläui
- Institute of Physics, Johannes Gutenberg-University Mainz, 55099, Mainz, Germany.
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10
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Tan AKC, Jani H, Högen M, Stefan L, Castelnovo C, Braund D, Geim A, Mechnich A, Feuer MSG, Knowles HS, Ariando A, Radaelli PG, Atatüre M. Revealing emergent magnetic charge in an antiferromagnet with diamond quantum magnetometry. NATURE MATERIALS 2024; 23:205-211. [PMID: 38052937 PMCID: PMC10837077 DOI: 10.1038/s41563-023-01737-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Accepted: 10/13/2023] [Indexed: 12/07/2023]
Abstract
Whirling topological textures play a key role in exotic phases of magnetic materials and are promising for logic and memory applications. In antiferromagnets, these textures exhibit enhanced stability and faster dynamics with respect to their ferromagnetic counterparts, but they are also difficult to study due to their vanishing net magnetic moment. One technique that meets the demand of highly sensitive vectorial magnetic field sensing with negligible backaction is diamond quantum magnetometry. Here we show that an archetypal antiferromagnet-haematite-hosts a rich tapestry of monopolar, dipolar and quadrupolar emergent magnetic charge distributions. The direct read-out of the previously inaccessible vorticity of an antiferromagnetic spin texture provides the crucial connection to its magnetic charge through a duality relation. Our work defines a paradigmatic class of magnetic systems to explore two-dimensional monopolar physics, and highlights the transformative role that diamond quantum magnetometry could play in exploring emergent phenomena in quantum materials.
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Affiliation(s)
- Anthony K C Tan
- Cavendish Laboratory, University of Cambridge, Cambridge, UK.
| | - Hariom Jani
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK.
- Department of Physics, National University of Singapore, Singapore, Singapore.
| | - Michael Högen
- Cavendish Laboratory, University of Cambridge, Cambridge, UK
| | - Lucio Stefan
- Cavendish Laboratory, University of Cambridge, Cambridge, UK
- Center for Hybrid Quantum Networks (Hy-Q), Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | | | - Daniel Braund
- Cavendish Laboratory, University of Cambridge, Cambridge, UK
| | - Alexandra Geim
- Cavendish Laboratory, University of Cambridge, Cambridge, UK
| | - Annika Mechnich
- Cavendish Laboratory, University of Cambridge, Cambridge, UK
| | | | | | - Ariando Ariando
- Department of Physics, National University of Singapore, Singapore, Singapore
| | - Paolo G Radaelli
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK.
| | - Mete Atatüre
- Cavendish Laboratory, University of Cambridge, Cambridge, UK.
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11
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Yu X, Kanazawa N, Zhang X, Takahashi Y, Iakoubovskii KV, Nakajima K, Tanigaki T, Mochizuki M, Tokura Y. Spontaneous Vortex-Antivortex Pairs and Their Topological Transitions in a Chiral-Lattice Magnet. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2306441. [PMID: 37712832 DOI: 10.1002/adma.202306441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 09/12/2023] [Indexed: 09/16/2023]
Abstract
The spontaneous formation and topological transitions of vortex-antivortex pairs have implications for a broad range of emergent phenomena, for example, from superconductivity to quantum computing. Unlike magnets exhibiting collinear spin textures, helimagnets with noncollinear spin textures provide unique opportunities to manipulate topological forms such as (anti)merons and (anti)skyrmions. However, it is challenging to achieve multiple topological states and their interconversion in a single helimagnet due to the topological protection for each state. Here, the on-demand creation of multiple topological states in a helimagnet Fe0.5 Co0.5 Ge, including a spontaneous vortex pair of meron with topological charge N = -1/2 and antimeron with N = 1/2, and a vortex-antivortex bundle, that is, a bimeron (meron pair) with N = -1 is reported. The mutual transformation between skyrmions and bimerons with respect to the competitive effects of magnetic field and magnetic shape anisotropy is demonstrated. It is shown that electric currents drive the individual bimerons to form their connecting assembly and then into a skyrmion lattice. These findings signify the feasibility of designing topological states and offer new insights into the manipulation of noncollinear spin textures for potential applications in various fields.
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Affiliation(s)
- Xiuzhen Yu
- RIKEN Center for Emergent Matter Science (CEMS), Wako, 351-0198, Japan
| | - Naoya Kanazawa
- Institute of Industrial Science, The University of Tokyo, Tokyo, 153-8505, Japan
| | - Xichao Zhang
- Department of Applied Physics, Waseda University, Tokyo, 169-8555, Japan
| | - Yoshio Takahashi
- Research and Development Group, Hitachi, Ltd., Hatoyama, 350-0395, Japan
| | | | - Kiyomi Nakajima
- RIKEN Center for Emergent Matter Science (CEMS), Wako, 351-0198, Japan
| | - Toshiaki Tanigaki
- Research and Development Group, Hitachi, Ltd., Hatoyama, 350-0395, Japan
| | - Masahito Mochizuki
- Department of Applied Physics, Waseda University, Tokyo, 169-8555, Japan
| | - Yoshinori Tokura
- RIKEN Center for Emergent Matter Science (CEMS), Wako, 351-0198, Japan
- Department of Applied Physics and Tokyo College, The University of Tokyo, Tokyo, 113-8656, Japan
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12
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Aldarawsheh A, Sallermann M, Abusaa M, Lounis S. Intrinsic Néel Antiferromagnetic Multimeronic Spin Textures in Ultrathin Films. J Phys Chem Lett 2023; 14:8970-8978. [PMID: 37773009 PMCID: PMC10577774 DOI: 10.1021/acs.jpclett.3c02419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 09/27/2023] [Indexed: 09/30/2023]
Abstract
Topological antiferromagnetism is a vibrant and captivating research field, generating considerable enthusiasm with the aim of identifying topologically protected magnetic states of key importance in the hybrid realm of topology, magnetism, and spintronics. While topological antiferromagnetic (AFM) solitons bear various advantages with respect to their ferromagnetic cousins, their observation is scarce. Utilizing first-principles simulations, here we predict new chiral particles in the realm of AFM topological magnetism, exchange-frustrated multimeronic spin textures hosted by a Néel magnetic state, arising universally in single Mn layers directly grown on an Ir(111) surface or interfaced with Pd-based films. These nanoscale topological structures are intrinsic; i.e. they form in a single AFM material, can carry distinct topological charges, and can combine in various multimeronic sequences with enhanced stability against external magnetic fields. We envision the frustrated Néel AFM multimerons as exciting highly sought after AFM solitons having the potential to be utilized in novel spintronic devices hinging on nonsynthetic AFM quantum materials, further advancing the frontiers of nanotechnology and nanophysics.
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Affiliation(s)
- Amal Aldarawsheh
- Peter
Grünberg Institute and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, D-52425 Jülich, Germany
- Faculty
of Physics, University of Duisburg-Essen
and CENIDE, 47053 Duisburg, Germany
| | - Moritz Sallermann
- Peter
Grünberg Institute and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, D-52425 Jülich, Germany
- RWTH
Aachen University, 52056 Aachen, Germany
- Science
Institute and Faculty of Physical Sciences, University of Iceland, VR-III, 107 Reykjavík, Iceland
| | - Muayad Abusaa
- Department
of Physics, Arab American University, 240 Jenin, Palestine
| | - Samir Lounis
- Peter
Grünberg Institute and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, D-52425 Jülich, Germany
- Faculty
of Physics, University of Duisburg-Essen
and CENIDE, 47053 Duisburg, Germany
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13
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Amin OJ, Poole SF, Reimers S, Barton LX, Dal Din A, Maccherozzi F, Dhesi SS, Novák V, Krizek F, Chauhan JS, Campion RP, Rushforth AW, Jungwirth T, Tretiakov OA, Edmonds KW, Wadley P. Antiferromagnetic half-skyrmions electrically generated and controlled at room temperature. NATURE NANOTECHNOLOGY 2023; 18:849-853. [PMID: 37157021 PMCID: PMC10427425 DOI: 10.1038/s41565-023-01386-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 03/24/2023] [Indexed: 05/10/2023]
Abstract
Topologically protected magnetic textures are promising candidates for information carriers in future memory devices, as they can be efficiently propelled at very high velocities using current-induced spin torques. These textures-nanoscale whirls in the magnetic order-include skyrmions, half-skyrmions (merons) and their antiparticles. Antiferromagnets have been shown to host versions of these textures that have high potential for terahertz dynamics, deflection-free motion and improved size scaling due to the absence of stray field. Here we show that topological spin textures, merons and antimerons, can be generated at room temperature and reversibly moved using electrical pulses in thin-film CuMnAs, a semimetallic antiferromagnet that is a testbed system for spintronic applications. The merons and antimerons are localized on 180° domain walls, and move in the direction of the current pulses. The electrical generation and manipulation of antiferromagnetic merons is a crucial step towards realizing the full potential of antiferromagnetic thin films as active components in high-density, high-speed magnetic memory devices.
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Affiliation(s)
- O J Amin
- School of Physics and Astronomy, University of Nottingham, Nottingham, UK.
| | - S F Poole
- School of Physics and Astronomy, University of Nottingham, Nottingham, UK
| | - S Reimers
- School of Physics and Astronomy, University of Nottingham, Nottingham, UK
- Diamond Light Source, Chilton, UK
- Institut für Physik, Johannes Gutenberg Universität Mainz, Mainz, Germany
| | - L X Barton
- School of Physics and Astronomy, University of Nottingham, Nottingham, UK
| | - A Dal Din
- School of Physics and Astronomy, University of Nottingham, Nottingham, UK
| | | | | | - V Novák
- Institute of Physics, Czech Academy of Sciences, Prague, Czech Republic
| | - F Krizek
- Institute of Physics, Czech Academy of Sciences, Prague, Czech Republic
| | - J S Chauhan
- School of Physics and Astronomy, University of Nottingham, Nottingham, UK
| | - R P Campion
- School of Physics and Astronomy, University of Nottingham, Nottingham, UK
| | - A W Rushforth
- School of Physics and Astronomy, University of Nottingham, Nottingham, UK
| | - T Jungwirth
- School of Physics and Astronomy, University of Nottingham, Nottingham, UK
- Institute of Physics, Czech Academy of Sciences, Prague, Czech Republic
| | - O A Tretiakov
- School of Physics, The University of New South Wales, Sydney, New South Wales, Australia
| | - K W Edmonds
- School of Physics and Astronomy, University of Nottingham, Nottingham, UK
| | - P Wadley
- School of Physics and Astronomy, University of Nottingham, Nottingham, UK
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14
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Gerasimchuk VS, Gorobets YI, Gorobets OY, Gerasimchuk IV. Spatial antiferromagnetic spin texture as a nano-oscillator. Sci Rep 2023; 13:6613. [PMID: 37095166 PMCID: PMC10126036 DOI: 10.1038/s41598-023-33220-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Accepted: 04/10/2023] [Indexed: 04/26/2023] Open
Abstract
We report a theoretical study of the localized spatial magnetization configuration, which is a confined spin configuration of the target skyrmion/hopfion type in an antiferromagnet with perpendicular magnetic anisotropy, and then we solve the particular problem of self-oscillations of such a topological spin texture. Using the energy approach, a self-consistent account of inhomogeneity of the characteristics of the topological magnetic spin texture was carried out. On this basis, the equation of free oscillations of the confined spin configuration magnetization was derived and its quasi-classical solution was found. For a thin ring spin texture, the frequency, period of oscillations and relative amplitude of the main tone of oscillations are found. For the first time, we determined the topological mass, inertial mass and total energy of the main tone of oscillations of such spatial spin texture. The self-oscillatory process of a spatial spin texture is interpreted as a magnetic nano-oscillator.
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Affiliation(s)
- Victor S Gerasimchuk
- Faculty of Physics and Mathematics, National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute", Peremohy Ave. 37, Kyiv, 03056, Ukraine
| | - Yuri I Gorobets
- Faculty of Physics and Mathematics, National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute", Peremohy Ave. 37, Kyiv, 03056, Ukraine
- Department of Physics of Meso- and Nanocrystal Magnetic Structures, Institute of Magnetism, National Academy of Sciences of Ukraine and Ministry of Education and Science of Ukraine, Vernadsky Blvd. 36b, Kyiv, 03142, Ukraine
| | - Oksana Yu Gorobets
- Faculty of Physics and Mathematics, National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute", Peremohy Ave. 37, Kyiv, 03056, Ukraine
- Department of Physics of Meso- and Nanocrystal Magnetic Structures, Institute of Magnetism, National Academy of Sciences of Ukraine and Ministry of Education and Science of Ukraine, Vernadsky Blvd. 36b, Kyiv, 03142, Ukraine
| | - Igor V Gerasimchuk
- Faculty of Physics and Mathematics, National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute", Peremohy Ave. 37, Kyiv, 03056, Ukraine.
- Department of Physics of Meso- and Nanocrystal Magnetic Structures, Institute of Magnetism, National Academy of Sciences of Ukraine and Ministry of Education and Science of Ukraine, Vernadsky Blvd. 36b, Kyiv, 03142, Ukraine.
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15
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Liu C, Li Z, Hu J, Duan H, Wang C, Cai L, Feng S, Wang Y, Liu R, Hou D, Liu C, Zhang R, Zhu L, Niu Y, Zakharov AA, Sheng Z, Yan W. Probing the Néel-Type Antiferromagnetic Order and Coherent Magnon-Exciton Coupling in Van Der Waals VPS 3. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023:e2300247. [PMID: 37071057 DOI: 10.1002/adma.202300247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 04/01/2023] [Indexed: 06/13/2023]
Abstract
2D van der Waals (vdW) antiferromagnets have received intensive attention due to their terahertz resonance, multilevel magnetic-order states, and ultrafast spin dynamics. However, accurately identifying their magnetic configuration still remains a challenge owing to the lack of net magnetization and insensitivity to external fields. In this work, the Néel-type antiferromagnetic (AFM) order in 2D antiferromagnet VPS3 with the out-of-plane anisotropy, which is demonstrated by the temperature-dependent spin-phonon coupling and second-harmonic generation (SHG), is experimentally probed. This long-range AFM order even persists at the ultrathin limit. Furthermore, strong interlayer exciton-magnon coupling (EMC) upon the Néel-type AFM order is detected based on the monolayer WSe2 /VPS3 heterostructure, which induces an enhanced excitonic state and further certifies the Néel-type AFM order of VPS3 . The discovery provides optical routes as the novel platform to study 2D antiferromagnets and promotes their potential applications in magneto-optics and opto-spintronic devices.
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Affiliation(s)
- Chaocheng Liu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, China
| | - Zhi Li
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, China
| | - Jiyu Hu
- Institute of Physical Science and Information Technology, Anhui University, Hefei, 230601, China
| | - Hengli Duan
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, China
| | - Chao Wang
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, China
| | - Liang Cai
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, China
| | - Sihua Feng
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, China
| | - Yao Wang
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, China
| | - Ruiqi Liu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, China
| | - De Hou
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
| | - Caixing Liu
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
| | - Ranran Zhang
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
| | - Lin Zhu
- MAX IV Laboratory, Lund University, Lund, 22100, Sweden
| | - Yuran Niu
- MAX IV Laboratory, Lund University, Lund, 22100, Sweden
| | | | - Zhigao Sheng
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
| | - Wensheng Yan
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, China
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16
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Rosales HD, Albarracín FAG, Pujol P, Jaubert LDC. Skyrmion Fluid and Bimeron Glass Protected by a Chiral Spin Liquid on a Kagome Lattice. PHYSICAL REVIEW LETTERS 2023; 130:106703. [PMID: 36962046 DOI: 10.1103/physrevlett.130.106703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 11/10/2022] [Accepted: 02/03/2023] [Indexed: 06/18/2023]
Abstract
Skyrmions are of interest both from a fundamental and technological point of view, due to their potential to act as information carriers. But one challenge concerns their manipulation, especially at high temperature where thermal fluctuations eventually disintegrate them. Here we study the competition between skyrmions and a chiral spin liquid, using the latter as an entropic buffer to impose a quasivacuum of skyrmions. As a result, the temperature becomes a knob to tune the skyrmion density from a dense liquid to a diluted gas, protecting the integrity of each skyrmion from paramagnetic disintegration. With this additional knob in hand, we find at high field a topological spin glass made of zero- and one-dimensional topological defects (respectively skyrmions and bimerons).
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Affiliation(s)
- H Diego Rosales
- Instituto de Física de Líquidos y Sistemas Biológicos, CONICET, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 1900 La Plata, Argentina
- Departamento de Física, FCE, UNLP, 1900 La Plata, Argentina
- Departamento de Ciencias Básicas, Facultad de Ingeniería, UNLP, 1900 La Plata, Argentina
| | - Flavia A Gómez Albarracín
- Instituto de Física de Líquidos y Sistemas Biológicos, CONICET, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 1900 La Plata, Argentina
- Departamento de Física, FCE, UNLP, 1900 La Plata, Argentina
- Departamento de Ciencias Básicas, Facultad de Ingeniería, UNLP, 1900 La Plata, Argentina
| | - Pierre Pujol
- Laboratoire de Physique Théorique, CNRS and Université de Toulouse, UPS, Toulouse, F-31062, France
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17
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Wang H, Yuan R, Zhou Y, Zhang Y, Chen J, Liu S, Jia H, Yu D, Ansermet JP, Song C, Yu H. Long-Distance Coherent Propagation of High-Velocity Antiferromagnetic Spin Waves. PHYSICAL REVIEW LETTERS 2023; 130:096701. [PMID: 36930935 DOI: 10.1103/physrevlett.130.096701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 01/06/2023] [Accepted: 02/10/2023] [Indexed: 06/18/2023]
Abstract
We report on coherent propagation of antiferromagnetic (AFM) spin waves over a long distance (∼10 μm) at room temperature in a canted AFM α-Fe_{2}O_{3} owing to the Dzyaloshinskii-Moriya interaction (DMI). Unprecedented high group velocities (up to 22.5 km/s) are characterized by microwave transmission using all-electrical spin wave spectroscopy. We derive analytically AFM spin-wave dispersion in the presence of the DMI which accounts for our experimental results. The AFM spin waves excited by nanometric coplanar waveguides have large wave vectors in the exchange regime and follow a quasilinear dispersion relation. Fitting of experimental data with our theoretical model yields an AFM exchange stiffness length of 1.7 Å. Our results provide key insights on AFM spin dynamics and demonstrate high-speed functionality for AFM magnonics.
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Affiliation(s)
- Hanchen Wang
- Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China
- International Quantum Academy, Shenzhen 518048, China
- Department of Materials, ETH Zurich, Zurich 8093, Switzerland
| | - Rundong Yuan
- Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China
| | - Yongjian Zhou
- Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
| | - Yuelin Zhang
- Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China
| | - Jilei Chen
- International Quantum Academy, Shenzhen 518048, China
- Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Song Liu
- International Quantum Academy, Shenzhen 518048, China
- Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Hao Jia
- International Quantum Academy, Shenzhen 518048, China
- Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Dapeng Yu
- International Quantum Academy, Shenzhen 518048, China
- Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Jean-Philippe Ansermet
- Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Cheng Song
- Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
| | - Haiming Yu
- Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China
- International Quantum Academy, Shenzhen 518048, China
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18
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Powalla L, Birch MT, Litzius K, Wintz S, Yasin FS, Turnbull LA, Schulz F, Mayoh DA, Balakrishnan G, Weigand M, Yu X, Kern K, Schütz G, Burghard M. Seeding and Emergence of Composite Skyrmions in a van der Waals Magnet. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2208930. [PMID: 36637996 DOI: 10.1002/adma.202208930] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 12/14/2022] [Indexed: 06/17/2023]
Abstract
Topological charge plays a significant role in a range of physical systems. In particular, observations of real-space topological objects in magnetic materials have been largely limited to skyrmions - states with a unitary topological charge. Recently, more exotic states with varying topology, such as antiskyrmions, merons, or bimerons and 3D states such as skyrmion strings, chiral bobbers, and hopfions, have been experimentally reported. Along these lines, the realization of states with higher-order topology has the potential to open new avenues of research in topological magnetism and its spintronic applications. Here, real-space imaging of such spin textures, including skyrmion, skyrmionium, skyrmion bag, and skyrmion sack states, observed in exfoliated flakes of the van der Waals magnet Fe3-x GeTe2 (FGT) is reported. These composite skyrmions may emerge from seeded, loop-like states condensed into the stripe domain structure, demonstrating the possibility to realize spin textures with arbitrary integer topological charge within exfoliated flakes of 2D magnets. The general nature of the formation mechanism motivates the search for composite skyrmion states in both well-known and new magnetic materials, which may yet reveal an even richer spectrum of higher-order topological objects.
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Affiliation(s)
- Lukas Powalla
- Max Planck Institute for Solid State Research, 70569, Stuttgart, Germany
| | - Max T Birch
- Max Planck Institute for Intelligent Systems, 70569, Stuttgart, Germany
- RIKEN Center for Emergent Matter Science (CEMS), Wako, 351-0198, Japan
| | - Kai Litzius
- Max Planck Institute for Intelligent Systems, 70569, Stuttgart, Germany
| | - Sebastian Wintz
- Max Planck Institute for Intelligent Systems, 70569, Stuttgart, Germany
| | - Fehmi S Yasin
- RIKEN Center for Emergent Matter Science (CEMS), Wako, 351-0198, Japan
| | - Luke A Turnbull
- Department of Physics, Durham University, Durham, DH1 3LE, UK
| | - Frank Schulz
- Max Planck Institute for Intelligent Systems, 70569, Stuttgart, Germany
| | - Daniel A Mayoh
- Department of Physics, University of Warwick, Coventry, CV4 7AL, UK
| | | | - Markus Weigand
- Institute Nanospectroscopy, Helmholtz-Zentrum Berlin, 12489, Berlin, Germany
| | - Xiuzhen Yu
- RIKEN Center for Emergent Matter Science (CEMS), Wako, 351-0198, Japan
| | - Klaus Kern
- Max Planck Institute for Solid State Research, 70569, Stuttgart, Germany
- Institut de Physique, École Polytechnique Fédérale de Lausanne, Lausanne, 1015, Switzerland
| | - Gisela Schütz
- Max Planck Institute for Intelligent Systems, 70569, Stuttgart, Germany
| | - Marko Burghard
- Max Planck Institute for Solid State Research, 70569, Stuttgart, Germany
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19
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Zhao Z, Fang Z, Han X, Yang S, Zhou C, Zeng Y, Zhang B, Li W, Wang Z, Zhang Y, Zhou J, Zhou J, Ye Y, Hou X, Zhao X, Gao S, Hou Y. A general thermodynamics-triggered competitive growth model to guide the synthesis of two-dimensional nonlayered materials. Nat Commun 2023; 14:958. [PMID: 36810290 PMCID: PMC9944324 DOI: 10.1038/s41467-023-36619-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Accepted: 02/08/2023] [Indexed: 02/23/2023] Open
Abstract
Two-dimensional (2D) nonlayered materials have recently provoked a surge of interest due to their abundant species and attractive properties with promising applications in catalysis, nanoelectronics, and spintronics. However, their 2D anisotropic growth still faces considerable challenges and lacks systematic theoretical guidance. Here, we propose a general thermodynamics-triggered competitive growth (TTCG) model providing a multivariate quantitative criterion to predict and guide 2D nonlayered materials growth. Based on this model, we design a universal hydrate-assisted chemical vapor deposition strategy for the controllable synthesis of various 2D nonlayered transition metal oxides. Four unique phases of iron oxides with distinct topological structures have also been selectively grown. More importantly, ultra-thin oxides display high-temperature magnetic ordering and large coercivity. MnxFeyCo3-x-yO4 alloy is also demonstrated to be a promising room-temperature magnetic semiconductor. Our work sheds light on the synthesis of 2D nonlayered materials and promotes their application for room-temperature spintronic devices.
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Affiliation(s)
- Zijing Zhao
- grid.11135.370000 0001 2256 9319School of Materials Science and Engineering, Beijing Key Laboratory for Magnetoelectric Materials and Devices, Beijing Innovation Center for Engineering Science and Advanced Technology, Peking University, Beijing, 100871 China ,grid.11135.370000 0001 2256 9319Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871 China
| | - Zhi Fang
- grid.11135.370000 0001 2256 9319School of Materials Science and Engineering, Beijing Key Laboratory for Magnetoelectric Materials and Devices, Beijing Innovation Center for Engineering Science and Advanced Technology, Peking University, Beijing, 100871 China
| | - Xiaocang Han
- grid.11135.370000 0001 2256 9319School of Materials Science and Engineering, Beijing Key Laboratory for Magnetoelectric Materials and Devices, Beijing Innovation Center for Engineering Science and Advanced Technology, Peking University, Beijing, 100871 China
| | - Shiqi Yang
- grid.11135.370000 0001 2256 9319State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-Optoelectronics, School of Physics, Peking University, Beijing, 100871 China
| | - Cong Zhou
- grid.43169.390000 0001 0599 1243Center for Alloy Innovation and Design, State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University, Xi’an, 710049 China
| | - Yi Zeng
- grid.11135.370000 0001 2256 9319School of Materials Science and Engineering, Beijing Key Laboratory for Magnetoelectric Materials and Devices, Beijing Innovation Center for Engineering Science and Advanced Technology, Peking University, Beijing, 100871 China
| | - Biao Zhang
- grid.11135.370000 0001 2256 9319School of Materials Science and Engineering, Beijing Key Laboratory for Magnetoelectric Materials and Devices, Beijing Innovation Center for Engineering Science and Advanced Technology, Peking University, Beijing, 100871 China
| | - Wei Li
- grid.11135.370000 0001 2256 9319School of Materials Science and Engineering, Beijing Key Laboratory for Magnetoelectric Materials and Devices, Beijing Innovation Center for Engineering Science and Advanced Technology, Peking University, Beijing, 100871 China
| | - Zhan Wang
- grid.9227.e0000000119573309Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190 China
| | - Ying Zhang
- grid.9227.e0000000119573309Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190 China
| | - Jian Zhou
- grid.43169.390000 0001 0599 1243Center for Alloy Innovation and Design, State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University, Xi’an, 710049 China
| | - Jiadong Zhou
- grid.43555.320000 0000 8841 6246Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement, School of Physics, Beijing Institute of Technology, Beijing, 100081 China
| | - Yu Ye
- grid.11135.370000 0001 2256 9319State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-Optoelectronics, School of Physics, Peking University, Beijing, 100871 China
| | - Xinmei Hou
- grid.69775.3a0000 0004 0369 0705Innovation Research Institute for Carbon Neutrality, University of Science and Technology Beijing, Beijing, 100083 China
| | - Xiaoxu Zhao
- School of Materials Science and Engineering, Beijing Key Laboratory for Magnetoelectric Materials and Devices, Beijing Innovation Center for Engineering Science and Advanced Technology, Peking University, Beijing, 100871, China.
| | - Song Gao
- grid.79703.3a0000 0004 1764 3838Institute of Spin-X Science and Technology, South China University of Technology, Guangzhou, 510641 China
| | - Yanglong Hou
- School of Materials Science and Engineering, Beijing Key Laboratory for Magnetoelectric Materials and Devices, Beijing Innovation Center for Engineering Science and Advanced Technology, Peking University, Beijing, 100871, China. .,Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871, China.
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20
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Yang J, Ma Y, Wang J, Wang J, Liu Q. Influence of magnetic structure on the performance of twisted skyrmion-based nano-oscillator. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2023; 35:145801. [PMID: 36735965 DOI: 10.1088/1361-648x/acb8f2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Accepted: 02/03/2023] [Indexed: 06/18/2023]
Abstract
The spin torque nano-oscillator (STNO), a nanosize microwave signal generator, have caught the attention of a number of researchers due to its obvious advantages. Recently a chiral bulk material with twisted skyrmion has been discovered in studies with different helicity degrees. In this work, we design a new STNO based on twisted skyrmion existing in free layers of magnetic tunnel junction structure. We first investigate the effect of the magnetic moment of fixed layer on the twisted skyrmion and frequency of STNO. Although the magnetic moment of fixed layer does not affect the state of the twisted skyrmion but affects the precession frequency of STNO. Later, the current, external magnetic field and Dzyaloshinskii-Moriya interaction strength are changed to regulate the oscillation frequency of STNO. Our result may be favorable for the design of new twisted skyrmion-based STNO.
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Affiliation(s)
- JinXia Yang
- Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000, People's Republic of China
- Key Laboratory for Special Function Materials and Structural Design of the Ministry of the Education, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Yunxu Ma
- Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000, People's Republic of China
- Key Laboratory for Special Function Materials and Structural Design of the Ministry of the Education, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Jianing Wang
- Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000, People's Republic of China
- Key Laboratory for Special Function Materials and Structural Design of the Ministry of the Education, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Jianbo Wang
- Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000, People's Republic of China
- Key Laboratory for Special Function Materials and Structural Design of the Ministry of the Education, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Qingfang Liu
- Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000, People's Republic of China
- Key Laboratory for Special Function Materials and Structural Design of the Ministry of the Education, Lanzhou University, Lanzhou 730000, People's Republic of China
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21
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Ly O. Noncollinear antiferromagnetic textures driven high-harmonic generation from magnetic dynamics in the absence of spin-orbit coupling. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2023; 35:125802. [PMID: 36669207 DOI: 10.1088/1361-648x/acb523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 01/20/2023] [Indexed: 06/17/2023]
Abstract
We demonstrate the generation of high order harmonics in carrier pumping from precessing ferromagnetic or antiferromagnetic orders, excited via magnetic resonance, in the presence of topological antiferromagnetic textures. This results in an enhancement of the carrier dynamics by orders of magnitude, enabling for an emission deep in the THz frequency range. Interestingly, the generation process occurs in an intrinsic manner, and is solely governed by the interplay between the s-d exchange coupling underlying the noncollinear antiferromagnetic order and the dynamical s-d exchange constant of the magnetic drive. Therefore, the relativistic spin-orbit interaction is not required for the emergence of high harmonics in the pumped currents. Accordingly, the noncollinear topological antiferromagnetic order is presented as an alternative to spin-orbit interaction for the purpose of harnessing high harmonic emission in carrier pumping. Furthermore, we demonstrate the emergence of high harmonics from random magnetic impurities. This suggests the universality of the magnetically induced high harmonic emission in the presence of real and/or momentum space noncollinear textures. Our proposal initiates a tantalizing prospect for the utilization of topological textures in the context of the highly active domains of ultrafast spintronics and THz emission.
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Affiliation(s)
- Ousmane Ly
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
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22
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Wu M, Wang H, Liang X, Wang D. Optimized electromagnetic wave absorption of α-Fe 2O 3@MoS 2nanocomposites with core-shell structure. NANOTECHNOLOGY 2023; 34:145703. [PMID: 36563351 DOI: 10.1088/1361-6528/acae29] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 12/22/2022] [Indexed: 06/17/2023]
Abstract
Core-shell structures and interfacial polarization are of great significance to meet the diversified requirements of microwave attenuation. Herein,α-Fe2O3@MoS2nanocomposites are fabricated via a simple two-step hydrothermal process, in which MoS2nanosheets as the shell are self-assembled andα-Fe2O3microdrums are used as the core to constitute a special flower-like morphology with core-shell structure. This structure can provide more interface contact to achieve strong interfacial polarization and possibly offer more multiple reflection and scattering of electromagnetic waves. Furthermore, the microwave dissipation performances ofα-Fe2O3@MoS2nanocomposites can be significantly improved through construction of core-shell structure and flower-like morphology, controlling the content ofα-Fe2O3microdrums and adjusting the filler loading ratios. This work proves that the as-synthesized nanocomposites achieve excellent effective absorption bandwidth and outstanding electromagnetic wave absorption capabilities due to their special interfaces, core-shell structures and good impedance matching conditions. Therefore,α-Fe2O3@MoS2nanocomposites are expected to be a novel and desirable candidate for high-performance electromagnetic wave absorbers.
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Affiliation(s)
- Mei Wu
- Hangzhou Dianzi University, Hangzhou, 310018, People's Republic of China
| | - Hongchang Wang
- Hangzhou Dianzi University, Hangzhou, 310018, People's Republic of China
| | - Xiaohui Liang
- Hangzhou Dianzi University, Hangzhou, 310018, People's Republic of China
| | - Dunhui Wang
- Hangzhou Dianzi University, Hangzhou, 310018, People's Republic of China
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23
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Aldarawsheh A, Fernandes IL, Brinker S, Sallermann M, Abusaa M, Blügel S, Lounis S. Emergence of zero-field non-synthetic single and interchained antiferromagnetic skyrmions in thin films. Nat Commun 2022; 13:7369. [DOI: 10.1038/s41467-022-35102-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 11/15/2022] [Indexed: 12/02/2022] Open
Abstract
AbstractAntiferromagnetic (AFM) skyrmions are envisioned as ideal localized topological magnetic bits in future information technologies. In contrast to ferromagnetic (FM) skyrmions, they are immune to the skyrmion Hall effect, might offer potential terahertz dynamics while being insensitive to external magnetic fields and dipolar interactions. Although observed in synthetic AFM structures and as complex meronic textures in intrinsic AFM bulk materials, their realization in non-synthetic AFM films, of crucial importance in racetrack concepts, has been elusive. Here, we unveil their presence in a row-wise AFM Cr film deposited on PdFe bilayer grown on fcc Ir(111) surface. Using first principles, we demonstrate the emergence of single and strikingly interpenetrating chains of AFM skyrmions, which can co-exist with the rich inhomogeneous exchange field, including that of FM skyrmions, hosted by PdFe. Besides the identification of an ideal platform of materials for intrinsic AFM skyrmions, we anticipate the uncovered knotted solitons to be promising building blocks in AFM spintronics.
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24
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Dou K, Du W, He Z, Dai Y, Huang B, Ma Y. Theoretical Prediction of Antiferromagnetic Skyrmion Crystal in Janus Monolayer CrSi 2N 2As 2. ACS NANO 2022; 17:1144-1152. [PMID: 36448916 DOI: 10.1021/acsnano.2c08544] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
An antiferromagnetic skyrmion crystal (AF-SkX), a regular array of antiferromagnetic skyrmions, is a fundamental phenomenon in the field of condensed-matter physics. So far, very few proposals have been made to realize the AF-SkX, and most have been based on three-dimensional (3D) materials. Herein, using first-principles calculations and Monte Carlo simulations, we report the identification of AF-SkX in a two-dimensional lattice of the Janus monolayer CrSi2N2As2. Arising from the broken inversion symmetry and strong spin-orbit coupling, a large Dzyaloshinskii-Moriya interaction is obtained in the Janus monolayer CrSi2N2As2. This, combined with the geometric frustration of its triangular lattice, gives rise to the skyrmion physics and long-sought AF-SkX in the presence of an external magnetic field. More intriguingly, this system presents two different antiferromagnetic skyrmion phases, and such a phenomenon is distinct from those reported in 3D systems. Furthermore, by contacting with Sc2CO2, the creation and annihilation of AF-SkX in Janus monolayer CrSi2N2As2 can be achieved through ferroelectricity. These findings greatly enrich the research on antiferromagnetic skyrmions.
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Affiliation(s)
- Kaiying Dou
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Shandanan Str. 27, Jinan250100, People's Republic of China
| | - Wenhui Du
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Shandanan Str. 27, Jinan250100, People's Republic of China
| | - Zhonglin He
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Shandanan Str. 27, Jinan250100, People's Republic of China
| | - Ying Dai
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Shandanan Str. 27, Jinan250100, People's Republic of China
| | - Baibiao Huang
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Shandanan Str. 27, Jinan250100, People's Republic of China
| | - Yandong Ma
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Shandanan Str. 27, Jinan250100, People's Republic of China
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25
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Juge R, Sisodia N, Larrañaga JU, Zhang Q, Pham VT, Rana KG, Sarpi B, Mille N, Stanescu S, Belkhou R, Mawass MA, Novakovic-Marinkovic N, Kronast F, Weigand M, Gräfe J, Wintz S, Finizio S, Raabe J, Aballe L, Foerster M, Belmeguenai M, Buda-Prejbeanu LD, Pelloux-Prayer J, Shaw JM, Nembach HT, Ranno L, Gaudin G, Boulle O. Skyrmions in synthetic antiferromagnets and their nucleation via electrical current and ultra-fast laser illumination. Nat Commun 2022; 13:4807. [PMID: 35974009 PMCID: PMC9381802 DOI: 10.1038/s41467-022-32525-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 08/03/2022] [Indexed: 11/09/2022] Open
Abstract
Magnetic skyrmions are topological spin textures that hold great promise as nanoscale information carriers in non-volatile memory and logic devices. While room-temperature magnetic skyrmions and their current-induced motion were recently demonstrated, the stray field resulting from their finite magnetisation and their topological charge limit their minimum size and reliable motion. Antiferromagnetic skyrmions allow to lift these limitations owing to their vanishing magnetisation and net zero topological charge, promising ultra-small and ultra-fast skyrmions. Here, we report on the observation of isolated skyrmions in compensated synthetic antiferromagnets at zero field and room temperature using X-ray magnetic microscopy. Micromagnetic simulations and an analytical model confirm the chiral antiferromagnetic nature of these skyrmions and allow the identification of the physical mechanisms controlling their size and stability. Finally, we demonstrate the nucleation of synthetic antiferromagnetic skyrmions via local current injection and ultra-fast laser excitation.
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Affiliation(s)
- Roméo Juge
- Univ. Grenoble Alpes, CNRS, CEA, SPINTEC, 38000, Grenoble, France
| | - Naveen Sisodia
- Univ. Grenoble Alpes, CNRS, CEA, SPINTEC, 38000, Grenoble, France
| | | | - Qiang Zhang
- Univ. Grenoble Alpes, CNRS, CEA, SPINTEC, 38000, Grenoble, France
| | - Van Tuong Pham
- Univ. Grenoble Alpes, CNRS, CEA, SPINTEC, 38000, Grenoble, France
| | | | - Brice Sarpi
- Synchrotron SOLEIL, L'Orme des Merisiers, 91190, Saint-Aubin, France
| | - Nicolas Mille
- Synchrotron SOLEIL, L'Orme des Merisiers, 91190, Saint-Aubin, France
| | - Stefan Stanescu
- Synchrotron SOLEIL, L'Orme des Merisiers, 91190, Saint-Aubin, France
| | - Rachid Belkhou
- Synchrotron SOLEIL, L'Orme des Merisiers, 91190, Saint-Aubin, France
| | - Mohamad-Assaad Mawass
- Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Straße 15, 12489, Berlin, Germany
| | - Nina Novakovic-Marinkovic
- Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Straße 15, 12489, Berlin, Germany
| | - Florian Kronast
- Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Straße 15, 12489, Berlin, Germany
| | - Markus Weigand
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, D-14109, Berlin, Germany
| | - Joachim Gräfe
- Max Planck Institute for Intelligent Systems, Heisenbergstraße 3, 70569, Stuttgart, Germany
| | - Sebastian Wintz
- Max Planck Institute for Intelligent Systems, Heisenbergstraße 3, 70569, Stuttgart, Germany
| | - Simone Finizio
- Swiss Light Source, Paul Scherrer Institut, 5232, Villigen, Switzerland
| | - Jörg Raabe
- Swiss Light Source, Paul Scherrer Institut, 5232, Villigen, Switzerland
| | - Lucia Aballe
- ALBA Synchrotron Light Facility, 08290, Cerdanyola del Vallès, Barcelona, Spain
| | - Michael Foerster
- ALBA Synchrotron Light Facility, 08290, Cerdanyola del Vallès, Barcelona, Spain
| | - Mohamed Belmeguenai
- Laboratoire des Sciences des Procedés et des Matériaux, CNRS, Univ. Paris 13, 93430, Villetaneuse, France
| | | | | | - Justin M Shaw
- Quantum Electromagnetics Division, National Institute of Standards and Technology, Boulder, CO, 80309, USA
| | - Hans T Nembach
- Quantum Electromagnetics Division, National Institute of Standards and Technology, Boulder, CO, 80309, USA.,Department of Physics, University of Colorado, Boulder, CO, 80309, USA
| | - Laurent Ranno
- Univ. Grenoble Alpes, CNRS, Institut Néel, 38042, Grenoble, France
| | - Gilles Gaudin
- Univ. Grenoble Alpes, CNRS, CEA, SPINTEC, 38000, Grenoble, France
| | - Olivier Boulle
- Univ. Grenoble Alpes, CNRS, CEA, SPINTEC, 38000, Grenoble, France.
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26
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Fujita R, Bassirian P, Li Z, Guo Y, Mawass MA, Kronast F, van der Laan G, Hesjedal T. Layer-Dependent Magnetic Domains in Atomically Thin Fe 5GeTe 2. ACS NANO 2022; 16:10545-10553. [PMID: 35802911 PMCID: PMC9331157 DOI: 10.1021/acsnano.2c01948] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Magnetic domain formation in two-dimensional (2D) materials gives perspectives into the fundamental origins of 2D magnetism and also motivates the development of advanced spintronics devices. However, the characterization of magnetic domains in atomically thin van der Waals (vdW) flakes remains challenging. Here, we employ X-ray photoemission electron microscopy (XPEEM) to perform layer-resolved imaging of the domain structures in the itinerant vdW ferromagnet Fe5GeTe2 which shows near room temperature bulk ferromagnetism and a weak perpendicular magnetic anisotropy (PMA). In the bulk limit, we observe the well-known labyrinth-type domains. Thinner flakes, on the other hand, are characterized by increasingly fragmented domains. While PMA is a characteristic property of Fe5GeTe2, we observe a spin-reorientation transition with the spins canting in-plane for flakes thinner than six layers. Notably, a bubble phase emerges in four-layer flakes. This thickness dependence, which clearly deviates from the single-domain behavior observed in other 2D magnetic materials, demonstrates the exciting prospect of stabilizing complex spin textures in 2D vdW magnets at relatively high temperatures.
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Affiliation(s)
- Ryuji Fujita
- Clarendon
Laboratory, Department of Physics, University
of Oxford, Parks Road, Oxford, OX1
3PU, United Kingdom
| | - Pedram Bassirian
- Clarendon
Laboratory, Department of Physics, University
of Oxford, Parks Road, Oxford, OX1
3PU, United Kingdom
- Max
Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany
| | - Zhengxian Li
- School
of Physical Science and Technology, ShanghaiTech
University, Shanghai 201210, China
| | - Yanfeng Guo
- School
of Physical Science and Technology, ShanghaiTech
University, Shanghai 201210, China
| | - Mohamad A. Mawass
- Helmholtz-Zentrum
Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - Florian Kronast
- Helmholtz-Zentrum
Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - Gerrit van der Laan
- Diamond
Light Source, Harwell Science and Innovation
Campus, Didcot, OX11 0DE, United Kingdom
| | - Thorsten Hesjedal
- Clarendon
Laboratory, Department of Physics, University
of Oxford, Parks Road, Oxford, OX1
3PU, United Kingdom
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27
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Abstract
A key issue for skyrmion dynamics and devices are pinning effects present in real systems. While posing a challenge for the realization of conventional skyrmionics devices, exploiting pinning effects can enable non-conventional computing approaches if the details of the pinning in real samples are quantified and understood. We demonstrate that using thermal skyrmion dynamics, we can characterize the pinning of a sample and we ascertain the spatially resolved energy landscape. To understand the mechanism of the pinning, we probe the strong skyrmion size and shape dependence of the pinning. Magnetic microscopy imaging demonstrates that in contrast to findings in previous investigations, for large skyrmions the pinning originates at the skyrmion boundary and not at its core. The boundary pinning is strongly influenced by the very complex pinning energy landscape that goes beyond the conventional effective rigid quasi-particle description. This gives rise to complex skyrmion shape distortions and allows for dynamic switching of pinning sites and flexible tuning of the pinning. Skyrmions, topological spin textures, can be pinned by defects present in the material that hosts them, influencing their motion. Here, Gruber et al show that the skyrmions are pinned at their boundary where the finite size of the skyrmions governs their pinning, and they demonstrate that certain pinning sites can switched on and off in-situ.
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28
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Cui Q, Zhu Y, Ga Y, Liang J, Li P, Yu D, Cui P, Yang H. Anisotropic Dzyaloshinskii-Moriya Interaction and Topological Magnetism in Two-Dimensional Magnets Protected by P4̅ m2 Crystal Symmetry. NANO LETTERS 2022; 22:2334-2341. [PMID: 35266723 DOI: 10.1021/acs.nanolett.1c04803] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
As a fundamental magnetic parameter, Dzyaloshinskii-Moriya interaction (DMI), has gained a great deal of attention in the last two decades due to its critical role in formation of magnetic skyrmions. Recent discoveries of two-dimensional (2D) van der Waals (vdW) magnets has also gained a great deal of attention due to appealing physical properties, such as gate tunability, flexibility, and miniaturization. Intensive studies have shown that isotropic DMI stabilizes ferromagnetic (FM) topological spin textures in 2D magnets or their corresponding heterostructures. However, the investigation of anisotropic DMI and antiferromagnetic (AFM) topological spin configurations remains elusive. Here, we propose and demonstrate a family of 2D magnets with P4m2 symmetry-protected anisotropic DMI. More interestingly, various topological spin configurations, including FM/AFM antiskyrmion and AFM vortex-antivortex pair, emerge in this family. These results give a general method to design anisotropic DMI and pave the way toward topological magnetism in 2D materials using crystal symmetry.
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Affiliation(s)
- Qirui Cui
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
- Faculty of Science and Engineering, University of Nottingham Ningbo China, Ningbo 315100, China
| | - Yingmei Zhu
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
| | - Yonglong Ga
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
| | - Jinghua Liang
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
| | - Peng Li
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
| | - Dongxing Yu
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
| | - Ping Cui
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
- Faculty of Science and Engineering, University of Nottingham Ningbo China, Ningbo 315100, China
| | - Hongxin Yang
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
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29
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Shen Z, Xue Y, Wu Z, Song C. Spontaneous magnetic merons in a half-metallic Mn 2I 3Br 3 monolayer with easy-plane anisotropy. Phys Chem Chem Phys 2022; 24:27612-27618. [DOI: 10.1039/d2cp03534k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Spontaneous magnetic merons are found to exist in a wide magnetic field range (0–6 T) stabilized by the large in-plane magnetic anisotropy and strong Dzyaloshinskii–Moriya interaction in a half-metallic Mn2I3Br3 monolayer.
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Affiliation(s)
- Zhong Shen
- Key Laboratory of Optical Field Manipulation of Zhejiang Province, Department of Physics, Zhejiang Sci-Tech University, Hangzhou, China
| | - Yufei Xue
- Key Laboratory of Optical Field Manipulation of Zhejiang Province, Department of Physics, Zhejiang Sci-Tech University, Hangzhou, China
| | - Zebin Wu
- Key Laboratory of Optical Field Manipulation of Zhejiang Province, Department of Physics, Zhejiang Sci-Tech University, Hangzhou, China
| | - Changsheng Song
- Key Laboratory of Optical Field Manipulation of Zhejiang Province, Department of Physics, Zhejiang Sci-Tech University, Hangzhou, China
- Longgang Institute of Zhejiang Sci-Tech University, Wenzhou, China
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30
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Zhao H, Porter Z, Chen X, Wilson SD, Wang Z, Zeljkovic I. Imaging antiferromagnetic domain fluctuations and the effect of atomic scale disorder in a doped spin-orbit Mott insulator. SCIENCE ADVANCES 2021; 7:eabi6468. [PMID: 34757784 PMCID: PMC8580306 DOI: 10.1126/sciadv.abi6468] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 09/20/2021] [Indexed: 06/13/2023]
Abstract
Correlated oxides can exhibit complex magnetic patterns. Understanding how magnetic domains form in the presence of disorder and their robustness to temperature variations has been of particular interest, but atomic scale insight has been limited. We use spin-polarized scanning tunneling microscopy to image the evolution of spin-resolved modulations originating from antiferromagnetic (AF) ordering in a spin-orbit Mott insulator perovskite iridate Sr3Ir2O7 as a function of chemical composition and temperature. We find that replacing only several percent of lanthanum for strontium leaves behind nanometer-scale AF puddles clustering away from lanthanum substitutions preferentially located in the middle strontium oxide layer. Thermal erasure and reentry into the low-temperature ground state leads to a spatial reorganization of the AF puddles, which nevertheless maintain scale-invariant fractal geometry in each configuration. Our experiments reveal multiple stable AF configurations at low temperature and shed light onto spatial fluctuations of the AF order around atomic scale disorder in electron-doped Sr3Ir2O7.
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Affiliation(s)
- He Zhao
- Department of Physics, Boston College, Chestnut Hill, MA 02467, USA
| | - Zach Porter
- Materials Department, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Xiang Chen
- Materials Department, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Stephen D. Wilson
- Materials Department, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Ziqiang Wang
- Department of Physics, Boston College, Chestnut Hill, MA 02467, USA
| | - Ilija Zeljkovic
- Department of Physics, Boston College, Chestnut Hill, MA 02467, USA
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31
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Chen X, Zheng C, Zhou S, Liu Y, Zhang Z. Ferromagnetic resonance modes of a synthetic antiferromagnet at low magnetic fields. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 34:015802. [PMID: 34571492 DOI: 10.1088/1361-648x/ac2a79] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 09/27/2021] [Indexed: 06/13/2023]
Abstract
One key advantage of antiferromagnets over ferromagnets is the high magnetic resonance frequencies that enable ultrafast magnetization switching and oscillations. Among a variety of antiferromagnets, the synthetic antiferromagnet (SAF) is a promising candidate for high-speed spintronic devices design. In this paper, micromagnetic simulations are employed to study the resonance modes in an SAF structure consisting of two identical CoFeB ferromagnetic (FM) layers that are antiferromagnetically coupled via interlayer exchange coupling. When the external bias magnetic field is small enough to ensure the magnetizations of two FM sublayers remain antiparallel alignments, we find that there exist two resonance modes with different precession chirality, namelyy-component synchronized mode andz-component synchronized mode, respectively. These two resonance modes show different features from the conventional in-phase acoustic mode and out-of-phase optic mode. The simulation results are in good agreement with our theoretical analyses.
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Affiliation(s)
- Xing Chen
- Key Laboratory of Micro and Nano Photonic Structures (MOE), School of Information Science and Technology, Fudan University, Shanghai 200433, People's Republic of China
| | - Cuixiu Zheng
- Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology, School of Physics Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China
| | - Sai Zhou
- Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology, School of Physics Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China
| | - Yaowen Liu
- Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology, School of Physics Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China
| | - Zongzhi Zhang
- Key Laboratory of Micro and Nano Photonic Structures (MOE), School of Information Science and Technology, Fudan University, Shanghai 200433, People's Republic of China
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32
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Huang C, Jiang LZ, Zhu Y, Pan YF, Fan JY, Ma CL, Hu J, Shi DN. Tuning Dzyaloshinskii-Moriya interaction via an electric field at the Co/h-BN interface. Phys Chem Chem Phys 2021; 23:22246-22250. [PMID: 34586123 DOI: 10.1039/d1cp02554f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The Dzyaloshinsky-Moriya interaction (DMI) at the Co/h-BN interface can emerge and be enhanced by applying a downward electric field. The height of the Co atom relative to the h-BN layer with the electric field determines the variation of DMI. One half reduction of J1 is beneficial to generate skyrmions. Tuning the DMI by an electric field sheds new light for research on skyrmions.
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Affiliation(s)
- C Huang
- College of Science, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China. .,MIIT Key Laboratory of Aerospace Information Materials and Physics, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China.
| | - L Z Jiang
- College of Science, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China. .,MIIT Key Laboratory of Aerospace Information Materials and Physics, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China.
| | - Y Zhu
- College of Science, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China. .,MIIT Key Laboratory of Aerospace Information Materials and Physics, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China.
| | - Y F Pan
- College of Science, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China. .,MIIT Key Laboratory of Aerospace Information Materials and Physics, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China.
| | - J Y Fan
- College of Science, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China. .,MIIT Key Laboratory of Aerospace Information Materials and Physics, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China.
| | - C L Ma
- Jiangsu Key Laboratory of Micro and Nano Heat Fluid Flow Technology and Energy Application, School of Physical Science and Technology, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - J Hu
- School of Physical Science and Technology, Ningbo University, Ningbo 315211, China.
| | - D N Shi
- College of Science, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China. .,MIIT Key Laboratory of Aerospace Information Materials and Physics, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China.
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33
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Haraguchi T, Otsubo K, Sakata O, Fujiwara A, Kitagawa H. Strain-Controlled Spin Transition in Heterostructured Metal-Organic Framework Thin Film. J Am Chem Soc 2021; 143:16128-16135. [PMID: 34514790 DOI: 10.1021/jacs.1c06662] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Metal-organic framework (MOF) thin films have recently attracted much attention as a new platform for surface/interface research, where unconventional structural and physical properties emerge. Among the many MOFs as candidates for fabrication of thin films, Hofmann-type MOFs {Fe(pz)[M(CN)4]} [pz = pyrazine; M = Ni (Nipz), M = Pt (Ptpz)] are attractive, because they undergo spin transitions with concomitant structural changes. Here, we demonstrate the first example of a strain-controlled spin transition in heterostructured MOF thin films. The spin transition temperature of Ptpz can be controlled in the temperature range of 300-380 K by fabricating a nanometer-sized heterostructured thin film with a Nipz buffer layer, where the smaller lattice of Nipz causes epitaxial compressive strain to the Ptpz layer. The fabricated heterostructured thin film exhibited a remarkable increase in spin transition temperature with a dynamic structural transformation, confirmed by variable-temperature (VT) X-ray diffraction and VT Raman spectroscopy. By verifying interfacial strain in a heterostructured thin film, we can rationally control the characteristics of MOFs-not only spin transition but also various physical properties such as gas storage, catalysis, sensing, proton conductivity, and electrical properties, among others.
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Affiliation(s)
- Tomoyuki Haraguchi
- Department of Chemistry, Graduate School of Science, Tokyo University of Science, 1-3 Kagurazaka, Sinjuku-ku, Tokyo 162-8601, Japan.,Division of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan
| | - Kazuya Otsubo
- Division of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan
| | - Osami Sakata
- Center for Synchrotron Radiation Research, Japan Synchrotron Radiation Research Institute (JASRI), Sayo-gun, Hyogo 679-5198, Japan
| | - Akihiko Fujiwara
- School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan
| | - Hiroshi Kitagawa
- Division of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan
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Kandukuri S, Murthy VSN, Thiruvikraman PK. Isolated skyrmion, skyrmion lattice and antiskyrmion lattice creation through magnetization reversal in Co/Pd nanostructure. Sci Rep 2021; 11:18945. [PMID: 34556719 PMCID: PMC8460664 DOI: 10.1038/s41598-021-98337-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Accepted: 08/30/2021] [Indexed: 11/09/2022] Open
Abstract
Skyrmion and antiskyrmion spin textures are axisymmetric inhomogeneous localized objects with distinct chirality in magnetic systems. These spin textures are potential candidates for the next generation energy-efficient spintronic applications due to their unique topological properties. Controlled and effective creation of the spin textures is required to use in conventional and neuromorphic computing applications. Here we show by micromagnetic simulations creating an isolated skyrmion, skyrmion lattice and antiskyrmion lattice through the magnetization reversal in Co/Pd multilayer nanostructure using spin-polarized current. The spin textures' stability depends on the spin-polarized current density, current pulse width, and Dzyaloshinskii-Moriya interaction (DMI). Antiskyrmions are evolved during the formation of a single skyrmion and skyrmion lattice. Skyrmion and antiskyrmion lattices together are observed for lower pulse width, 0.05 ns. Our micromagnetic studies suggest that the two distinct lattice phases' evolution could help to design the topological spin textures-based devices.
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Affiliation(s)
- Sateesh Kandukuri
- Department of Physics, BITS Pilani Hyderabad Campus, Jawahar Nagar, Kapra Mandal, Medchal District, Hyderabad, 500078, Telangana, India
| | - V Satya Narayana Murthy
- Department of Physics, BITS Pilani Hyderabad Campus, Jawahar Nagar, Kapra Mandal, Medchal District, Hyderabad, 500078, Telangana, India.
| | - P K Thiruvikraman
- Department of Physics, BITS Pilani Hyderabad Campus, Jawahar Nagar, Kapra Mandal, Medchal District, Hyderabad, 500078, Telangana, India
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35
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Shen Y. Topological bimeronic beams. OPTICS LETTERS 2021; 46:3737-3740. [PMID: 34329269 DOI: 10.1364/ol.431122] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 06/29/2021] [Indexed: 05/28/2023]
Abstract
This Letter proposes a family of structured light, called bimeronic beams, that characterize topological structures of bimeron (the quasiparticle homeomorphic to skyrmion). The polarization Stokes vectors of bimeronic beams emulate bimeron structures, which are reconfigurable to form various topological textures by tuning mode parameters. The bimeronic beams unveil a mechanism to transform diverse topological states of light, similar to the skyrmionic transformations among Néel, Bloch, and anti-skyrmion types. Moreover, bimeronic transformations are more generalized to include skyrmionic transformations as special cases.
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36
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Reversible hydrogen control of antiferromagnetic anisotropy in α-Fe 2O 3. Nat Commun 2021; 12:1668. [PMID: 33712582 PMCID: PMC7954816 DOI: 10.1038/s41467-021-21807-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 02/04/2021] [Indexed: 11/14/2022] Open
Abstract
Antiferromagnetic insulators are a ubiquitous class of magnetic materials, holding the promise of low-dissipation spin-based computing devices that can display ultra-fast switching and are robust against stray fields. However, their imperviousness to magnetic fields also makes them difficult to control in a reversible and scalable manner. Here we demonstrate a novel proof-of-principle ionic approach to control the spin reorientation (Morin) transition reversibly in the common antiferromagnetic insulator α-Fe2O3 (haematite) – now an emerging spintronic material that hosts topological antiferromagnetic spin-textures and long magnon-diffusion lengths. We use a low-temperature catalytic-spillover process involving the post-growth incorporation or removal of hydrogen from α-Fe2O3 thin films. Hydrogenation drives pronounced changes in its magnetic anisotropy, Néel vector orientation and canted magnetism via electron injection and local distortions. We explain these effects with a detailed magnetic anisotropy model and first-principles calculations. Tailoring our work for future applications, we demonstrate reversible control of the room-temperature spin-state by doping/expelling hydrogen in Rh-substituted α-Fe2O3. One major challenge for antiferromagnetic spintronics is how to control the antiferromagnetic state. Here Jani et al. demonstrate the reversible ionic control of the room-temperature magnetic anisotropy and spin reorientation transition in haematite, via the incorporation and removal of hydrogen.
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