1
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Castell-Queralt J, Abad-López G, González-Gómez L, Del-Valle N, Navau C. Survival of skyrmions along granular racetracks at room temperature. Nanoscale Adv 2023; 5:4728-4734. [PMID: 37705781 PMCID: PMC10496888 DOI: 10.1039/d3na00464c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 07/27/2023] [Indexed: 09/15/2023]
Abstract
Skyrmions can be envisioned as bits of information that can be transported along nanoracetracks. However, temperature, defects, and/or granularity can produce diffusion, pinning, and, in general, modification in their dynamics. These effects may cause undesired errors in information transport. We present simulations of a realistic system where both the (room) temperature and sample granularity are taken into account. Key feasibility magnitudes, such as the success probability of a skyrmion traveling a given distance along the racetrack, are calculated. The results are evaluated in terms of the eventual loss of skyrmions by pinning, destruction at the edges, or excessive delay due to granularity. The model proposed is based on the Fokker-Planck equation resulting from Thiele's rigid model for skyrmions. The results could serve to establish error detection criteria and, in general, to discern the dynamics of skyrmions in realistic situations.
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Affiliation(s)
- Josep Castell-Queralt
- Departament de Física, Universitat Autònoma de Barcelona 08193 Bellaterra Barcelona Catalonia Spain
| | - Guillermo Abad-López
- Departament de Física, Universitat Autònoma de Barcelona 08193 Bellaterra Barcelona Catalonia Spain
| | - Leonardo González-Gómez
- Departament de Física, Universitat Autònoma de Barcelona 08193 Bellaterra Barcelona Catalonia Spain
| | - Nuria Del-Valle
- Departament de Física, Universitat Autònoma de Barcelona 08193 Bellaterra Barcelona Catalonia Spain
| | - Carles Navau
- Departament de Física, Universitat Autònoma de Barcelona 08193 Bellaterra Barcelona Catalonia Spain
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2
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Liu C, Zhang S, Maier SA, Ren H. Disorder-Induced Topological State Transition in the Optical Skyrmion Family. Phys Rev Lett 2022; 129:267401. [PMID: 36608180 DOI: 10.1103/physrevlett.129.267401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 12/07/2022] [Indexed: 06/17/2023]
Abstract
Skyrmions endowed with topological protection have been extensively investigated in various platforms including magnetics, ferroelectrics, and liquid crystals, stimulating applications such as memories, logic devices, and neuromorphic computing. While the optical counterpart has been proposed and realized recently, the study of optical skyrmions is still in its infancy. Among the unexplored questions, the investigation of the topology induced robustness against disorder is of substantial importance on both fundamental and practical sides but remains elusive. In this Letter, we manage to generate optical skyrmions numerically in real space with different topological features at will, providing a unique platform to investigate the robustness of various optical skyrmions. A disorder-induced topological state transition is observed for the first time in a family of optical skyrmions composed of six classes with different skyrmion numbers. Intriguingly, the optical skyrmions produced from a vectorial hologram are exceptionally robust against scattering from a random medium, shedding light on topological photonic devices for the generation and manipulation of robust states for applications including imaging and communication.
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Affiliation(s)
- Changxu Liu
- Department of Mathematics, Physics and Electrical Engineering, Northumbria University, Newcastle Upon Tyne NE1 8ST, United Kingdom and Chair in Hybrid Nanosystems, Nanoinstitute Munich, Faculty of Physics, Ludwig-Maximilians-Universitaet Muenchen, 80539 Muenchen, Germany
| | - Shuang Zhang
- Department of Physics, University of Hong Kong, Hong Kong, China and Department of Electrical Engineering, University of Hong Kong, Hong Kong, China
| | - Stefan A Maier
- School of Physics and Astronomy, Monash University, Clayton, Victoria 3800, Australia; Chair in Hybrid Nanosystems, Nanoinstitute Munich, Faculty of Physics, Ludwig-Maximilians-Universitaet Muenchen, 80539 Muenchen, Germany; and Department of Physics, Imperial College London, London SW7 2AZ, United Kingdom
| | - Haoran Ren
- School of Physics and Astronomy, Monash University, Clayton, Victoria 3800, Australia
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3
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Zhao L, Wang Z, Zhang X, Liang X, Xia J, Wu K, Zhou HA, Dong Y, Yu G, Wang KL, Liu X, Zhou Y, Jiang W. Topology-Dependent Brownian Gyromotion of a Single Skyrmion. Phys Rev Lett 2020; 125:027206. [PMID: 32701308 DOI: 10.1103/physrevlett.125.027206] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 06/02/2020] [Accepted: 06/18/2020] [Indexed: 06/11/2023]
Abstract
Noninteracting particles exhibiting Brownian motion have been observed in many occasions of sciences, such as molecules suspended in liquids, optically trapped microbeads, and spin textures in magnetic materials. In particular, a detailed examination of Brownian motion of spin textures is important for designing thermally stable spintronic devices, which motivates the present study. In this Letter, through using temporally and spatially resolved polar magneto-optic Kerr effect microscopy, we have experimentally observed the thermal fluctuation-induced random walk of a single isolated Néel-type magnetic skyrmion in an interfacially asymmetric Ta/CoFeB/TaO_{x} multilayer. An intriguing topology-dependent Brownian gyromotion behavior of skyrmions has been identified. The onset of Brownian gyromotion of a single skyrmion induced by thermal effects, including a nonlinear temperature-dependent diffusion coefficient and topology-dependent gyromotion are further formulated based on the stochastic Thiele equation. The experimental and numerical demonstration of topology-dependent Brownian gyromotion of skyrmions can be useful for understanding the nonequilibrium magnetization dynamics and implementing spintronic devices.
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Affiliation(s)
- Le Zhao
- State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Tsinghua University, Beijing 100084, China
| | - Zidong Wang
- State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Tsinghua University, Beijing 100084, China
| | - Xichao Zhang
- 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
| | - Jing Xia
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, China
| | - Keyu Wu
- State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Tsinghua University, Beijing 100084, China
| | - Heng-An Zhou
- State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Tsinghua University, Beijing 100084, China
| | - Yiqing Dong
- State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Tsinghua University, Beijing 100084, China
| | - Guoqiang Yu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Kang L Wang
- Department of Electrical Engineering, University of California, Los Angeles, California 90095, USA
| | - Xiaoxi Liu
- Department of Electrical and Computer Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan
| | - Yan Zhou
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, China
| | - Wanjun Jiang
- State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Tsinghua University, Beijing 100084, China
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4
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Friesen C, Osterhage H, Friedlein J, Schlenhoff A, Wiesendanger R, Krause S. Magneto-Seebeck tunneling on the atomic scale. Science 2019; 363:1065-1067. [DOI: 10.1126/science.aat7234] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 02/06/2019] [Indexed: 11/02/2022]
Abstract
The tunneling of spin-polarized electrons across a magnetic tunnel junction driven by a temperature gradient is a fundamental process for the thermal control of electron spin transport. We experimentally investigated the atomic-scale details of this magneto-Seebeck tunneling by placing a magnetic probe tip in close proximity to a magnetic sample at cryogenic temperature, with a vacuum as the tunneling barrier. Heating the tip and measuring the thermopower of the junction while scanning across the spin texture of the sample lead to spin-resolved Seebeck coefficients that can be mapped at atomic-scale lateral resolution. We propose a spin detector for spintronics applications that is driven solely by waste heat, using magneto-Seebeck tunneling to convert spin information into a voltage that can be used for further data processing.
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5
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Haze M, Yang HH, Asakawa K, Watanabe N, Yamamoto R, Yoshida Y, Hasegawa Y. Bulk ferromagnetic tips for spin-polarized scanning tunneling microscopy. Rev Sci Instrum 2019; 90:013704. [PMID: 30709171 DOI: 10.1063/1.5063759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 01/08/2019] [Indexed: 06/09/2023]
Abstract
We characterized the performance of electrochemically etched bulk Fe and Ni tips as a probe of spin-polarized scanning tunneling microscopy (SP-STM). Through the observation of the striped contrast on the conical spin-spiral structure formed in Mn double layers on a W(110) substrate, the capability of both the tips to detect the magnetic signal was clarified. We also confirmed that the magnetized direction of the Fe and Ni tips can be flipped between the two out-of-plane directions by external magnetic fields. Our results demonstrate that the ex-situ prepared tips are reliable in SP-STM for the samples that are not susceptible to a stray magnetic field.
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Affiliation(s)
- Masahiro Haze
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Hung-Hsiang Yang
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Kanta Asakawa
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Nobuyuki Watanabe
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Ryosuke Yamamoto
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Yasuo Yoshida
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Yukio Hasegawa
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
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6
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Zhang X, Cai W, Zhang X, Wang Z, Li Z, Zhang Y, Cao K, Lei N, Kang W, Zhang Y, Yu H, Zhou Y, Zhao W. Skyrmions in Magnetic Tunnel Junctions. ACS Appl Mater Interfaces 2018; 10:16887-16892. [PMID: 29682962 DOI: 10.1021/acsami.8b03812] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In this work, we demonstrate that skyrmions can be nucleated in the free layer of a magnetic tunnel junction (MTJ) with Dzyaloshinskii-Moriya interactions (DMIs) by a spin-polarized current with the assistance of stray fields from the pinned layer. The size, stability, and number of created skyrmions can be tuned by either the DMI strength or the stray field distribution. The interaction between the stray field and the DMI effective field is discussed. A device with multilevel tunneling magnetoresistance is proposed, which could pave the ways for skyrmion-MTJ-based multibit storage and artificial neural network computation. Our results may facilitate the efficient nucleation and electrical detection of skyrmions.
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Affiliation(s)
- Xueying Zhang
- Fert Beijing Institute, BDBC, School of Electronic and Information Engineering , Beihang University , Beijing 100191 , China
- Beihang-Goertek Joint Microelectronics Institute, Qingdao Research Institute , Beihang University , Qingdao 266101 , China
| | - Wenlong Cai
- Fert Beijing Institute, BDBC, School of Electronic and Information Engineering , Beihang University , Beijing 100191 , China
| | - Xichao Zhang
- School of Science and Engineering , The Chinese University of Hong Kong , Shenzhen 518172 , China
| | - Zilu Wang
- Fert Beijing Institute, BDBC, School of Electronic and Information Engineering , Beihang University , Beijing 100191 , China
| | - Zhi Li
- Fert Beijing Institute, BDBC, School of Electronic and Information Engineering , Beihang University , Beijing 100191 , China
- Beihang-Goertek Joint Microelectronics Institute, Qingdao Research Institute , Beihang University , Qingdao 266101 , China
| | - Yu Zhang
- Fert Beijing Institute, BDBC, School of Electronic and Information Engineering , Beihang University , Beijing 100191 , China
| | - Kaihua Cao
- Fert Beijing Institute, BDBC, School of Electronic and Information Engineering , Beihang University , Beijing 100191 , China
| | - Na Lei
- Fert Beijing Institute, BDBC, School of Electronic and Information Engineering , Beihang University , Beijing 100191 , China
- Beihang-Goertek Joint Microelectronics Institute, Qingdao Research Institute , Beihang University , Qingdao 266101 , China
| | - Wang Kang
- Fert Beijing Institute, BDBC, School of Electronic and Information Engineering , Beihang University , Beijing 100191 , China
| | - Yue Zhang
- Fert Beijing Institute, BDBC, School of Electronic and Information Engineering , Beihang University , Beijing 100191 , China
| | - Haiming Yu
- Fert Beijing Institute, BDBC, School of Electronic and Information Engineering , Beihang University , Beijing 100191 , China
| | - Yan Zhou
- School of Science and Engineering , The Chinese University of Hong Kong , Shenzhen 518172 , China
| | - Weisheng Zhao
- Fert Beijing Institute, BDBC, School of Electronic and Information Engineering , Beihang University , Beijing 100191 , China
- Beihang-Goertek Joint Microelectronics Institute, Qingdao Research Institute , Beihang University , Qingdao 266101 , China
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7
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Bordács S, Butykai A, Szigeti BG, White JS, Cubitt R, Leonov AO, Widmann S, Ehlers D, von Nidda HAK, Tsurkan V, Loidl A, Kézsmárki I. Equilibrium Skyrmion Lattice Ground State in a Polar Easy-plane Magnet. Sci Rep 2017; 7:7584. [PMID: 28790441 PMCID: PMC5548730 DOI: 10.1038/s41598-017-07996-x] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 07/04/2017] [Indexed: 11/09/2022] Open
Abstract
The skyrmion lattice state (SkL), a crystal built of mesoscopic spin vortices, gains its stability via thermal fluctuations in all bulk skyrmion host materials known to date. Therefore, its existence is limited to a narrow temperature region below the paramagnetic state. This stability range can drastically increase in systems with restricted geometries, such as thin films, interfaces and nanowires. Thermal quenching can also promote the SkL as a metastable state over extended temperature ranges. Here, we demonstrate more generally that a proper choice of material parameters alone guarantees the thermodynamic stability of the SkL over the full temperature range below the paramagnetic state down to zero kelvin. We found that GaV4Se8, a polar magnet with easy-plane anisotropy, hosts a robust Néel-type SkL even in its ground state. Our supporting theory confirms that polar magnets with weak uniaxial anisotropy are ideal candidates to realize SkLs with wide stability ranges.
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Affiliation(s)
- S Bordács
- Department of Physics, Budapest University of Technology and Economics and MTA-BME Lendület Magneto-optical Spectroscopy Research Group, 1111, Budapest, Hungary
| | - A Butykai
- Department of Physics, Budapest University of Technology and Economics and MTA-BME Lendület Magneto-optical Spectroscopy Research Group, 1111, Budapest, Hungary
| | - B G Szigeti
- Department of Physics, Budapest University of Technology and Economics and MTA-BME Lendület Magneto-optical Spectroscopy Research Group, 1111, Budapest, Hungary
| | - J S White
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232, Villigen, Switzerland
| | - R Cubitt
- Institut Laue-Langevin, 6 rue Jules Horowitz, 38042, Grenoble, France
| | - A O Leonov
- Center for Chiral Science, Hiroshima University, Higashi-Hiroshima, Hiroshima, 739-8526, Japan.,Department of Chemistry, Faculty of Science, Hiroshima University Kagamiyama, Higashi Hiroshima, Hiroshima, 739-8526, Japan
| | - S Widmann
- Experimental Physics V, Center for Electronic Correlations and Magnetism, University of Augsburg, 86135, Augsburg, Germany
| | - D Ehlers
- Experimental Physics V, Center for Electronic Correlations and Magnetism, University of Augsburg, 86135, Augsburg, Germany
| | - H-A Krug von Nidda
- Experimental Physics V, Center for Electronic Correlations and Magnetism, University of Augsburg, 86135, Augsburg, Germany
| | - V Tsurkan
- Experimental Physics V, Center for Electronic Correlations and Magnetism, University of Augsburg, 86135, Augsburg, Germany.,Institute of Applied Physics, Academy of Sciences of Moldova, MD, 2028, Chisinau, Republic of Moldova
| | - A Loidl
- Experimental Physics V, Center for Electronic Correlations and Magnetism, University of Augsburg, 86135, Augsburg, Germany
| | - I Kézsmárki
- Department of Physics, Budapest University of Technology and Economics and MTA-BME Lendület Magneto-optical Spectroscopy Research Group, 1111, Budapest, Hungary. .,Experimental Physics V, Center for Electronic Correlations and Magnetism, University of Augsburg, 86135, Augsburg, Germany.
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8
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Finco A, Rózsa L, Hsu PJ, Kubetzka A, Vedmedenko E, von Bergmann K, Wiesendanger R. Temperature-Induced Increase of Spin Spiral Periods. Phys Rev Lett 2017; 119:037202. [PMID: 28777635 DOI: 10.1103/physrevlett.119.037202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Indexed: 06/07/2023]
Abstract
Spin-polarized scanning tunneling microscopy investigations reveal a significant increase of the magnetic period of spin spirals in three-atomic-layer-thick Fe films on Ir(111), from about 4 nm at 8 K to about 65 nm at room temperature. We attribute this considerable influence of temperature on the magnetic length scale of noncollinear spin states to different exchange interaction coefficients in the different Fe layers. We thus propose a classical spin model that reproduces the experimental observations and in which the crucial feature is the presence of magnetically coupled atomic layers with different interaction strengths. This model might also apply for many other systems, especially magnetic multilayers.
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Affiliation(s)
- Aurore Finco
- Department of Physics, University of Hamburg, D-20355 Hamburg, Germany
| | - Levente Rózsa
- Department of Physics, University of Hamburg, D-20355 Hamburg, Germany
- Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest, Hungary
| | - Pin-Jui Hsu
- Department of Physics, University of Hamburg, D-20355 Hamburg, Germany
| | - André Kubetzka
- Department of Physics, University of Hamburg, D-20355 Hamburg, Germany
| | - Elena Vedmedenko
- Department of Physics, University of Hamburg, D-20355 Hamburg, Germany
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9
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Hagemeister J, Iaia D, Vedmedenko EY, von Bergmann K, Kubetzka A, Wiesendanger R. Skyrmions at the Edge: Confinement Effects in Fe/Ir(111). Phys Rev Lett 2016; 117:207202. [PMID: 27886488 DOI: 10.1103/physrevlett.117.207202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Indexed: 06/06/2023]
Abstract
We have employed spin-polarized scanning tunneling microscopy and Monte Carlo simulations to investigate the effect of lateral confinement onto the nano-Skyrmion lattice in Fe/Ir(111). We find a strong coupling of one diagonal of the square magnetic unit cell to the close-packed edges of Fe nanostructures. In triangular islands this coupling in combination with the mismatching symmetries of the islands and of the square nano-Skyrmion lattice leads to frustration and triple-domain states. In direct vicinity to ferromagnetic NiFe islands, the surrounding Skyrmion lattice forms additional domains. In this case a side of the square magnetic unit cell prefers a parallel orientation to the ferromagnetic edge. These experimental findings can be reproduced and explained by Monte Carlo simulations. Here, the single-domain state of a triangular island is lower in energy, but nevertheless multidomain states occur due to the combined effect of entropy and an intrinsic domain wall pinning arising from the skyrmionic character of the spin texture.
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Affiliation(s)
| | - Davide Iaia
- Department of Physics, University of Hamburg, D-20355 Hamburg, Germany
| | | | | | - André Kubetzka
- Department of Physics, University of Hamburg, D-20355 Hamburg, Germany
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10
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Boulle O, Vogel J, Yang H, Pizzini S, de Souza Chaves D, Locatelli A, Menteş TO, Sala A, Buda-Prejbeanu LD, Klein O, Belmeguenai M, Roussigné Y, Stashkevich A, Chérif SM, Aballe L, Foerster M, Chshiev M, Auffret S, Miron IM, Gaudin G. Room-temperature chiral magnetic skyrmions in ultrathin magnetic nanostructures. Nat Nanotechnol 2016; 11:449-454. [PMID: 26809057 DOI: 10.1038/nnano.2015.315] [Citation(s) in RCA: 226] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 12/01/2015] [Indexed: 06/05/2023]
Abstract
Magnetic skyrmions are chiral spin structures with a whirling configuration. Their topological properties, nanometre size and the fact that they can be moved by small current densities have opened a new paradigm for the manipulation of magnetization at the nanoscale. Chiral skyrmion structures have so far been experimentally demonstrated only in bulk materials and in epitaxial ultrathin films, and under an external magnetic field or at low temperature. Here, we report on the observation of stable skyrmions in sputtered ultrathin Pt/Co/MgO nanostructures at room temperature and zero external magnetic field. We use high lateral resolution X-ray magnetic circular dichroism microscopy to image their chiral Néel internal structure, which we explain as due to the large strength of the Dzyaloshinskii-Moriya interaction as revealed by spin wave spectroscopy measurements. Our results are substantiated by micromagnetic simulations and numerical models, which allow the identification of the physical mechanisms governing the size and stability of the skyrmions.
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Affiliation(s)
- Olivier Boulle
- Univ. Grenoble Alpes, SPINTEC, Grenoble F-38000, France
- CNRS, SPINTEC, Grenoble F-38000, France
- CEA, INAC-SPINTEC, Grenoble F-38000, France
| | - Jan Vogel
- CNRS, Institut Néel, 25 avenue des Martyrs, B.P. 166, Grenoble Cedex 9 38042, France
- Univ. Grenoble Alpes, Institut Néel, 25 avenue des Martyrs, B.P. 166, Grenoble Cedex 9 38042, France
| | - Hongxin Yang
- Univ. Grenoble Alpes, SPINTEC, Grenoble F-38000, France
- CNRS, SPINTEC, Grenoble F-38000, France
- CEA, INAC-SPINTEC, Grenoble F-38000, France
| | - Stefania Pizzini
- CNRS, Institut Néel, 25 avenue des Martyrs, B.P. 166, Grenoble Cedex 9 38042, France
- Univ. Grenoble Alpes, Institut Néel, 25 avenue des Martyrs, B.P. 166, Grenoble Cedex 9 38042, France
| | - Dayane de Souza Chaves
- CNRS, Institut Néel, 25 avenue des Martyrs, B.P. 166, Grenoble Cedex 9 38042, France
- Univ. Grenoble Alpes, Institut Néel, 25 avenue des Martyrs, B.P. 166, Grenoble Cedex 9 38042, France
| | - Andrea Locatelli
- Elettra-Sincrotrone, S.C.p.A, S.S 14 - km 163.5 in AREA Science Park 34149 Basovizza, Trieste, Italy
| | - Tevfik Onur Menteş
- Elettra-Sincrotrone, S.C.p.A, S.S 14 - km 163.5 in AREA Science Park 34149 Basovizza, Trieste, Italy
| | - Alessandro Sala
- Elettra-Sincrotrone, S.C.p.A, S.S 14 - km 163.5 in AREA Science Park 34149 Basovizza, Trieste, Italy
| | - Liliana D Buda-Prejbeanu
- Univ. Grenoble Alpes, SPINTEC, Grenoble F-38000, France
- CNRS, SPINTEC, Grenoble F-38000, France
- CEA, INAC-SPINTEC, Grenoble F-38000, France
| | - Olivier Klein
- Univ. Grenoble Alpes, SPINTEC, Grenoble F-38000, France
- CNRS, SPINTEC, Grenoble F-38000, France
- CEA, INAC-SPINTEC, Grenoble F-38000, France
| | - Mohamed Belmeguenai
- LSPM (CNRS-UPR 3407), Université Paris 13, Sorbonne Paris Cité, 99 avenue Jean-Baptiste Clément, Villetaneuse 93430, France
| | - Yves Roussigné
- LSPM (CNRS-UPR 3407), Université Paris 13, Sorbonne Paris Cité, 99 avenue Jean-Baptiste Clément, Villetaneuse 93430, France
| | - Andrey Stashkevich
- LSPM (CNRS-UPR 3407), Université Paris 13, Sorbonne Paris Cité, 99 avenue Jean-Baptiste Clément, Villetaneuse 93430, France
| | - Salim Mourad Chérif
- LSPM (CNRS-UPR 3407), Université Paris 13, Sorbonne Paris Cité, 99 avenue Jean-Baptiste Clément, Villetaneuse 93430, France
| | - Lucia Aballe
- ALBA Synchrotron Light Facility, Carretera BP 1413, Km. 3.3, Cerdanyola del Vallès, Barcelona 08290, Spain
| | - Michael Foerster
- ALBA Synchrotron Light Facility, Carretera BP 1413, Km. 3.3, Cerdanyola del Vallès, Barcelona 08290, Spain
| | - Mairbek Chshiev
- Univ. Grenoble Alpes, SPINTEC, Grenoble F-38000, France
- CNRS, SPINTEC, Grenoble F-38000, France
- CEA, INAC-SPINTEC, Grenoble F-38000, France
| | - Stéphane Auffret
- Univ. Grenoble Alpes, SPINTEC, Grenoble F-38000, France
- CNRS, SPINTEC, Grenoble F-38000, France
- CEA, INAC-SPINTEC, Grenoble F-38000, France
| | - Ioan Mihai Miron
- Univ. Grenoble Alpes, SPINTEC, Grenoble F-38000, France
- CNRS, SPINTEC, Grenoble F-38000, France
- CEA, INAC-SPINTEC, Grenoble F-38000, France
| | - Gilles Gaudin
- Univ. Grenoble Alpes, SPINTEC, Grenoble F-38000, France
- CNRS, SPINTEC, Grenoble F-38000, France
- CEA, INAC-SPINTEC, Grenoble F-38000, France
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11
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Hsu PJ, Finco A, Schmidt L, Kubetzka A, von Bergmann K, Wiesendanger R. Guiding Spin Spirals by Local Uniaxial Strain Relief. Phys Rev Lett 2016; 116:017201. [PMID: 26799040 DOI: 10.1103/physrevlett.116.017201] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Indexed: 06/05/2023]
Abstract
We report on the influence of uniaxial strain relief on the spin spiral state in the Fe double layer grown on Ir(111). Scanning tunneling microscopy (STM) measurements reveal areas with reconstruction lines resulting from uniaxial strain relief due to the lattice mismatch of Fe and Ir atoms, as well as pseudomorphic strained areas. Magnetic field-dependent spin-polarized STM measurements of the reconstructed Fe double layer reveal cycloidal spin spirals with a period on the nm scale. Globally, the spin spiral wave fronts are guided along symmetry-equivalent [112̅] crystallographic directions of the fcc(111) substrate. On an atomic scale the spin spiral propagation direction is linked to the [001] direction of the bcc(110)-like Fe, leading to a zigzag shaped wave front. The isotropically strained pseudomorphic areas also exhibit a preferred magnetic periodicity on the nm scale but no long-range order. We find that already for local strain relief with a single set of reconstruction lines a strict guiding of the spin spiral is realized.
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Affiliation(s)
- Pin-Jui Hsu
- Department of Physics, University of Hamburg, D-20355 Hamburg, Germany
| | - Aurore Finco
- Department of Physics, University of Hamburg, D-20355 Hamburg, Germany
- Département de physique, École normale supérieure, 45 rue d'Ulm, 75005 Paris, France
| | - Lorenz Schmidt
- Department of Physics, University of Hamburg, D-20355 Hamburg, Germany
| | - André Kubetzka
- Department of Physics, University of Hamburg, D-20355 Hamburg, Germany
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Schlenhoff A, Lindner P, Friedlein J, Krause S, Wiesendanger R, Weinl M, Schreck M, Albrecht M. Magnetic Nano-skyrmion Lattice Observed in a Si-Wafer-Based Multilayer System. ACS Nano 2015; 9:5908-5912. [PMID: 25964990 DOI: 10.1021/acsnano.5b01146] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Growth, electronic properties, and magnetic properties of an Fe monolayer (ML) on an Ir/YSZ/Si(111) multilayer system have been studied using spin-polarized scanning tunneling microscopy. Our experiments reveal a magnetic nano-skyrmion lattice, which is fully equivalent to the magnetic ground state that has previously been observed for the Fe ML on Ir(111) bulk single crystals. In addition, the experiments indicate that the interface-stabilized skyrmion lattice is robust against local atomic lattice distortions induced by multilayer preparation.
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Affiliation(s)
- Anika Schlenhoff
- †Department of Physics, University of Hamburg, Jungiusstraße 11, 20355 Hamburg, Germany
| | - Philipp Lindner
- †Department of Physics, University of Hamburg, Jungiusstraße 11, 20355 Hamburg, Germany
| | - Johannes Friedlein
- †Department of Physics, University of Hamburg, Jungiusstraße 11, 20355 Hamburg, Germany
| | - Stefan Krause
- †Department of Physics, University of Hamburg, Jungiusstraße 11, 20355 Hamburg, Germany
| | - Roland Wiesendanger
- †Department of Physics, University of Hamburg, Jungiusstraße 11, 20355 Hamburg, Germany
| | - Michael Weinl
- ‡Institute of Physics, University of Augsburg, Universitätsstraße 1, 86135 Augsburg, Germany
| | - Matthias Schreck
- ‡Institute of Physics, University of Augsburg, Universitätsstraße 1, 86135 Augsburg, Germany
| | - Manfred Albrecht
- ‡Institute of Physics, University of Augsburg, Universitätsstraße 1, 86135 Augsburg, Germany
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Abstract
Spin-resolved scanning tunneling microscopy is used to reveal a commensurate hexagonal nanoskyrmion lattice in the hcp stacked Fe monolayer on Ir(111). The exact nature of the spin configuration is due to magnetic interactions between the Fe atoms and the Ir substrate, either originating from polarization effects, or due to a three-site hopping mechanism of the Dzyaloshinsky-Moriya interaction leading to a canting of the Dzyaloshinsky-Moriya vector with respect to the interface.
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Affiliation(s)
| | - Matthias Menzel
- Department of Physics, University of Hamburg, 20355 Hamburg, Germany
| | - André Kubetzka
- Department of Physics, University of Hamburg, 20355 Hamburg, Germany
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Streubel R, Han L, Im MY, Kronast F, Rößler UK, Radu F, Abrudan R, Lin G, Schmidt OG, Fischer P, Makarov D. Manipulating topological states by imprinting non-collinear spin textures. Sci Rep 2015; 5:8787. [PMID: 25739643 DOI: 10.1038/srep08787] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 01/29/2015] [Indexed: 11/16/2022] Open
Abstract
Topological magnetic states, such as chiral skyrmions, are of great scientific interest and show huge potential for novel spintronics applications, provided their topological charges can be fully controlled. So far skyrmionic textures have been observed in noncentrosymmetric crystalline materials with low symmetry and at low temperatures. We propose theoretically and demonstrate experimentally the design of spin textures with topological charge densities that can be tailored at ambient temperatures. Tuning the interlayer coupling in vertically stacked nanopatterned magnetic heterostructures, such as a model system of a Co/Pd multilayer coupled to Permalloy, the in-plane non-collinear spin texture of one layer can be imprinted into the out-of-plane magnetised material. We observe distinct spin textures, e.g. vortices, magnetic swirls with tunable opening angle, donut states and skyrmion core configurations. We show that applying a small magnetic field, a reliable switching between topologically distinct textures can be achieved at remanence.
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