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Shi S, Zhao Y, Sun J, Yu G, Zhou H, Wang J. Strain-mediated multistate skyrmion for neuron devices. NANOSCALE 2024; 16:12013-12020. [PMID: 38805240 DOI: 10.1039/d4nr01464b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Magnetic skyrmions are potential candidates for neuromorphic computing because of their inherent topological stability, low drive current density and nanoscale size. However, an artificial neuron device based on current-driven skyrmion motion cannot satisfy the requirement of energy efficiency and integration density due to hundreds of millions of interconnected neurons and synapses present in the deep networks. Here, we present a compact and energy efficient skyrmion-based artificial neuron consisting of ferromagnetic/heavy metal/ferroelectric layers which uses strain-mediated voltage manipulation of skyrmion states to mimic the Integrate-and-Fire (IF) function of biological neurons. By implementation of a spiking neural network (SNN) based on the proposed skyrmionic neuronal devices, it can achieve a high accuracy of 95.08% on a modified National Institute of Standards and Technology (MNIST) handwritten digit dataset, as well as a low power consumption of ∼46.8 fJ per epoch per neuron. The present work suggests a novel way to realize energy-efficient and high-density neuromorphic computing.
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Affiliation(s)
- Shengbin Shi
- Department of Engineering Mechanics, Zhejiang University, Zheda Road 38, Hangzhou, Zhejiang 310027, China.
| | - Yunhong Zhao
- Zhejiang Laboratory, Hangzhou 311100, Zhejiang, China
| | - Jiajun Sun
- Department of Engineering Mechanics, Zhejiang University, Zheda Road 38, Hangzhou, Zhejiang 310027, China.
| | - Guoliang Yu
- Key Laboratory of Electromagnetic Wave Information Technology and Metrology of Zhejiang Province, College of Information Engineering, China Jiliang University, Hangzhou 310018, People's Republic of China
| | - Haomiao Zhou
- Key Laboratory of Electromagnetic Wave Information Technology and Metrology of Zhejiang Province, College of Information Engineering, China Jiliang University, Hangzhou 310018, People's Republic of China
| | - Jie Wang
- Department of Engineering Mechanics, Zhejiang University, Zheda Road 38, Hangzhou, Zhejiang 310027, China.
- Zhejiang Laboratory, Hangzhou 311100, Zhejiang, China
- Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province, Zhejiang University, Zheda Road 38, Hangzhou, Zhejiang 310027, China
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2
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Li R, Jin C, Zhang X, Qu J, Zheng D, He W, Yang F, Zheng R, Bai H. Angular-dependent magnetoresistance modulated by interfacial magnetic state in Pt/LSMO heterostructures. Phys Chem Chem Phys 2024; 26:16891-16897. [PMID: 38833218 DOI: 10.1039/d4cp01175a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2024]
Abstract
The interfaces between heavy metals and antiferromagnetic materials have garnered significant attention due to their interesting physical properties. La0.35Sr0.65MnO3 (LSMO), as a typical manganite, exhibits an antiferromagnetic ground state that can be controlled through epitaxial strain and interfacial spin-orbit coupling. In this work, we reported the diverse magnetoresistance, influenced by the interfacial magnetic state, in Pt (3 nm)/LSMO (6-20 nm) heterostructures. The strong spin-orbit coupling of Pt and Dzyaloshinskii-Moriya interaction alter the spin structure and enhance the electron scattering at the Pt/LSMO interface, resulting in positive magnetoresistance. The interfacial angular-dependent magnetoresistance modulated by the interfacial magnetic states was also observed in the Pt/LSMO (20 nm) heterostructures. Our findings contribute to a broader understanding of interfacial properties between heavy metals and antiferromagnetic manganites.
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Affiliation(s)
- Ruikang Li
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Processing Technology, School of Science, Tianjin University, Tianjin 300350, China.
| | - Chao Jin
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Processing Technology, School of Science, Tianjin University, Tianjin 300350, China.
| | - Xingmo Zhang
- School of Physics, The University of Sydney, Sydney, NSW 2006, Australia
| | - Jiangtao Qu
- Australian Centre for Microscopy & Microanalysis, The University of Sydney, Sydney, NSW 2006, Australia
| | - Dongxing Zheng
- Physical Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
| | - Wenxue He
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Processing Technology, School of Science, Tianjin University, Tianjin 300350, China.
- Center for Joint Quantum Studies, School of Science, Tianjin University, Tianjin 300350, China
| | - Fan Yang
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Processing Technology, School of Science, Tianjin University, Tianjin 300350, China.
- Center for Joint Quantum Studies, School of Science, Tianjin University, Tianjin 300350, China
| | - Rongkun Zheng
- School of Physics, The University of Sydney, Sydney, NSW 2006, Australia
| | - Haili Bai
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Processing Technology, School of Science, Tianjin University, Tianjin 300350, China.
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3
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Liu L, Wang D, Wang D, Sun Y, Lin H, Gong X, Zhang Y, Tang R, Mai Z, Hou Z, Yang Y, Li P, Wang L, Luo Q, Li L, Xing G, Liu M. Domain wall magnetic tunnel junction-based artificial synapses and neurons for all-spin neuromorphic hardware. Nat Commun 2024; 15:4534. [PMID: 38806482 PMCID: PMC11133408 DOI: 10.1038/s41467-024-48631-4] [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: 09/25/2023] [Accepted: 05/06/2024] [Indexed: 05/30/2024] Open
Abstract
We report a breakthrough in the hardware implementation of energy-efficient all-spin synapse and neuron devices for highly scalable integrated neuromorphic circuits. Our work demonstrates the successful execution of all-spin synapse and activation function generator using domain wall-magnetic tunnel junctions. By harnessing the synergistic effects of spin-orbit torque and interfacial Dzyaloshinskii-Moriya interaction in selectively etched spin-orbit coupling layers, we achieve a programmable multi-state synaptic device with high reliability. Our first-principles calculations confirm that the reduced atomic distance between 5d and 3d atoms enhances Dzyaloshinskii-Moriya interaction, leading to stable domain wall pinning. Our experimental results, supported by visualizing energy landscapes and theoretical simulations, validate the proposed mechanism. Furthermore, we demonstrate a spin-neuron with a sigmoidal activation function, enabling high operation frequency up to 20 MHz and low energy consumption of 508 fJ/operation. A neuron circuit design with a compact sigmoidal cell area and low power consumption is also presented, along with corroborated experimental implementation. Our findings highlight the great potential of domain wall-magnetic tunnel junctions in the development of all-spin neuromorphic computing hardware, offering exciting possibilities for energy-efficient and scalable neural network architectures.
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Affiliation(s)
- Long Liu
- Key Lab of Fabrication Technologies for Integrated Circuits, Institute of Microelectronics, Chinese Academy of Sciences, Beijing, 100029, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Di Wang
- Key Lab of Fabrication Technologies for Integrated Circuits, Institute of Microelectronics, Chinese Academy of Sciences, Beijing, 100029, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Dandan Wang
- Hubei Jiufengshan Laboratory, Wuhan, Hubei, 430206, China.
| | - Yan Sun
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, 110016, China
| | - Huai Lin
- Key Lab of Fabrication Technologies for Integrated Circuits, Institute of Microelectronics, Chinese Academy of Sciences, Beijing, 100029, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiliang Gong
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, 110016, China
| | - Yifan Zhang
- Key Lab of Fabrication Technologies for Integrated Circuits, Institute of Microelectronics, Chinese Academy of Sciences, Beijing, 100029, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ruifeng Tang
- Key Lab of Fabrication Technologies for Integrated Circuits, Institute of Microelectronics, Chinese Academy of Sciences, Beijing, 100029, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhihong Mai
- Hubei Jiufengshan Laboratory, Wuhan, Hubei, 430206, China
| | - Zhipeng Hou
- Institute for Advanced Materials, South China Normal University, Guangzhou, 510006, China
| | - Yumeng Yang
- School of Information Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Peng Li
- School of Microelectronics, University of Science and Technology of China, Hefei, 230026, China
| | - Lan Wang
- Lab of Low Dimensional Magnetism and Spintronic Devices, School of Physics, Hefei University of Technology, Hefei, 230009, Anhui, China
| | - Qing Luo
- Key Lab of Fabrication Technologies for Integrated Circuits, Institute of Microelectronics, Chinese Academy of Sciences, Beijing, 100029, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ling Li
- Key Lab of Fabrication Technologies for Integrated Circuits, Institute of Microelectronics, Chinese Academy of Sciences, Beijing, 100029, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Guozhong Xing
- Key Lab of Fabrication Technologies for Integrated Circuits, Institute of Microelectronics, Chinese Academy of Sciences, Beijing, 100029, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Ming Liu
- Key Lab of Fabrication Technologies for Integrated Circuits, Institute of Microelectronics, Chinese Academy of Sciences, Beijing, 100029, China.
- Frontier Institute of Chip and System, State Key Laboratory of Integrated Chips and Systems, Zhangjiang Fudan International Innovation Center, Fudan University, Shanghai, 200433, China.
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4
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Yang H, Li S, Wu Y, Bao X, Xiang Z, Xie Y, Pan L, Chen J, Liu Y, Li RW. Advances in Flexible Magnetosensitive Materials and Devices for Wearable Electronics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2311996. [PMID: 38776537 DOI: 10.1002/adma.202311996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 05/14/2024] [Indexed: 05/25/2024]
Abstract
Emerging fields, such as wearable electronics, digital healthcare, the Internet of Things, and humanoid robots, highlight the need for flexible devices capable of recording signals on curved surfaces and soft objects. In particular, flexible magnetosensitive devices garner significant attention owing to their ability to combine the advantages of flexible electronics and magnetoelectronic devices, such as reshaping capability, conformability, contactless sensing, and navigation capability. Several key challenges must be addressed to develop well-functional flexible magnetic devices. These include determining how to make magnetic materials flexible and even elastic, understanding how the physical properties of magnetic films change under external strain and stress, and designing and constructing flexible magnetosensitive devices. In recent years, significant progress is made in addressing these challenges. This study aims to provide a timely and comprehensive overview of the most recent developments in flexible magnetosensitive devices. This includes discussions on the fabrications and mechanical regulations of flexible magnetic materials, the principles and performances of flexible magnetic sensors, and their applications for wearable electronics. In addition, future development trends and challenges in this field are discussed.
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Affiliation(s)
- Huali Yang
- CAS Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
- Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
| | - Shengbin Li
- CAS Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
- Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
| | - Yuanzhao Wu
- CAS Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
- Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
| | - Xilai Bao
- CAS Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
- Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
- College of Materials Sciences and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Ziyin Xiang
- CAS Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
- Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
| | - Yali Xie
- CAS Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
- Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
| | - Lili Pan
- CAS Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
- Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
- College of Materials Sciences and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Jinxia Chen
- CAS Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
- Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
- College of Materials Sciences and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Yiwei Liu
- CAS Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
- Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
- College of Materials Sciences and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Run-Wei Li
- CAS Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
- Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China
- College of Materials Sciences and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
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5
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Meng Y, Meng F, Hou M, Zheng Q, Wang B, Zhu R, Feng C, Yu G. Regulation of interfacial Dzyaloshinskii-Moriya interaction in ferromagnetic multilayers. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2024; 36:193001. [PMID: 38286006 DOI: 10.1088/1361-648x/ad2386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 01/29/2024] [Indexed: 01/31/2024]
Abstract
Interfacial Dzyaloshinskii-Moriya interaction (i-DMI) exists in the film materials with inversion symmetry breaking, which can stabilize a series of nonlinear spin structures and control their chirality, such as Néel-type domain wall, magnetic skyrmion and spin spiral. In addition, the strength and chirality of i-DMI are directly related to the dynamic behavior of these nonlinear spin structures. Therefore, regulating the strength and chirality of i-DMI not only has an important scientific significance for enriching spintronics and topological physics, but also has a significant practical value for constructing a new generation of memorizer, logic gate, and brain-like devices with low-power. This review summarizes the research progress on the regulation of i-DMI in ferromagnetic films and provides some prospects for future research.
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Affiliation(s)
- Yufei Meng
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, People's Republic of China
| | - Fei Meng
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, People's Republic of China
| | - Mingxuan Hou
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, People's Republic of China
| | - Qianqi Zheng
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, People's Republic of China
| | - Boyi Wang
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, People's Republic of China
| | - Ronggui Zhu
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, People's Republic of China
| | - Chun Feng
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, People's Republic of China
| | - Guanghua Yu
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, People's Republic of China
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6
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Li S, Lin X, Li P, Zhao S, Si Z, Wei G, Koopmans B, Lavrijsen R, Zhao W. Ultralow Power and Shifting-Discretized Magnetic Racetrack Memory Device Driven by Chirality Switching and Spin Current. ACS APPLIED MATERIALS & INTERFACES 2023; 15:39946-39955. [PMID: 37581258 DOI: 10.1021/acsami.3c06447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/16/2023]
Abstract
Magnetic racetrack memory has significantly evolved and developed since its first experimental verification and is considered one of the most promising candidates for future high-density on-chip solid-state memory. However, both the lack of a fast and precise magnetic domain wall (DW) shifting mechanism and the required extremely high DW motion (DWM) driving current make the racetrack difficult to commercialize. Here, we propose a method for coherent DWM that is free from the above issues, which is driven by chirality switching (CS) and an ultralow spin-orbit-torque (SOT) current. The CS, as the driving force of DWM, is achieved by the sign change of the Dzyaloshinskii-Moriya interaction, which is further induced by a ferroelectric switching voltage. The SOT is used to break the symmetry when the magnetic moment is rotated in the Bloch direction. We numerically investigate the underlying principle and the effect of key parameters on the DWM by micromagnetic simulations. Under the CS mechanism, a fast (∼102 m/s), ultralow energy (∼5 attoJoule), and precisely discretized DWM can be achieved. Considering that skyrmions with topological protection and smaller size are also promising for future racetracks, we similarly evaluate the feasibility of applying such a CS mechanism to a skyrmion. However, we find that the CS causes it to "breathe" instead of moving. Our results demonstrate that the CS strategy is suitable for future DW racetrack memory with ultralow power consumption and discretized DWM.
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Affiliation(s)
- Shen Li
- School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China
- Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
- Hefei Innovation Research Institute, Beihang University, Hefei 230013, China
| | - Xiaoyang Lin
- School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China
- Hefei Innovation Research Institute, Beihang University, Hefei 230013, China
| | - Pingzhi Li
- Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
| | - Suteng Zhao
- School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China
| | - Zhizhong Si
- School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China
| | - Guodong Wei
- School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China
| | - Bert Koopmans
- Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
| | - Reinoud Lavrijsen
- Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
| | - Weisheng Zhao
- School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China
- Hefei Innovation Research Institute, Beihang University, Hefei 230013, China
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7
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Han MG, Camino F, Vorobyev PA, Garlow J, Rov R, Söhnel T, Seidel J, Mostovoy M, Tretiakov OA, Zhu Y. Hysteretic Responses of Skyrmion Lattices to Electric Fields in Magnetoelectric Cu 2OSeO 3. NANO LETTERS 2023; 23:7143-7149. [PMID: 37523664 DOI: 10.1021/acs.nanolett.3c02034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Abstract
Electric field control of topologically nontrivial magnetic textures, such as skyrmions, provides a paradigm shift for future spintronics beyond the current silicon-based technology. While significant progress has been made by X-ray and neutron scattering studies, direct observation of such nanoscale spin structures and their dynamics driven by external electric fields remains a challenge in understanding the underlying mechanisms and harness functionalities. Here, using Lorentz transmission electron microscopy combined with in situ electric and magnetic fields at liquid helium temperatures, we report the crystallographic orientation-dependent skyrmion responses to electric fields in thin slabs of magnetoelectric Cu2OSeO3. We show that electric fields not only stabilize the hexagonally packed skyrmion lattices in the entire sample in a hysteretic manner but also induce the rotation of their reciprocal vector discretely by 30°. The nonvolatile and energy-efficient skyrmion lattice control by electric fields demonstrated in this work provides an important foundation for designing skyrmion-based qubits and memory devices.
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Affiliation(s)
- Myung-Geun Han
- Condensed Matter Physics & Materials Science, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Fernando Camino
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Pavel A Vorobyev
- School of Physics, The University of New South Wales, Sydney 2052, Australia
| | - Joseph Garlow
- Condensed Matter Physics & Materials Science, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Rosanna Rov
- School of Chemical Sciences, University of Auckland, Auckland 1142, New Zealand
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6012, New Zealand
| | - Tilo Söhnel
- School of Chemical Sciences, University of Auckland, Auckland 1142, New Zealand
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6012, New Zealand
| | - Jan Seidel
- Department of Materials Science and Engineering, The University of New South Wales, Sydney 2052, Australia
| | - Maxim Mostovoy
- Department of Physics, University of Groningen, Groningen 9747, The Netherlands
| | - Oleg A Tretiakov
- School of Physics, The University of New South Wales, Sydney 2052, Australia
| | - Yimei Zhu
- Condensed Matter Physics & Materials Science, Brookhaven National Laboratory, Upton, New York 11973, United States
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8
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Sun Y, Lin T, Lei N, Chen X, Kang W, Zhao Z, Wei D, Chen C, Pang S, Hu L, Yang L, Dong E, Zhao L, Liu L, Yuan Z, Ullrich A, Back CH, Zhang J, Pan D, Zhao J, Feng M, Fert A, Zhao W. Experimental demonstration of a skyrmion-enhanced strain-mediated physical reservoir computing system. Nat Commun 2023; 14:3434. [PMID: 37301906 DOI: 10.1038/s41467-023-39207-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 06/02/2023] [Indexed: 06/12/2023] Open
Abstract
Physical reservoirs holding intrinsic nonlinearity, high dimensionality, and memory effects have attracted considerable interest regarding solving complex tasks efficiently. Particularly, spintronic and strain-mediated electronic physical reservoirs are appealing due to their high speed, multi-parameter fusion and low power consumption. Here, we experimentally realize a skyrmion-enhanced strain-mediated physical reservoir in a multiferroic heterostructure of Pt/Co/Gd multilayers on (001)-oriented 0.7PbMg1/3Nb2/3O3-0.3PbTiO3 (PMN-PT). The enhancement is coming from the fusion of magnetic skyrmions and electro resistivity tuned by strain simultaneously. The functionality of the strain-mediated RC system is successfully achieved via a sequential waveform classification task with the recognition rate of 99.3% for the last waveform, and a Mackey-Glass time series prediction task with normalized root mean square error (NRMSE) of 0.2 for a 20-step prediction. Our work lays the foundations for low-power neuromorphic computing systems with magneto-electro-ferroelastic tunability, representing a further step towards developing future strain-mediated spintronic applications.
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Affiliation(s)
- Yiming Sun
- Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing, 100191, China
| | - Tao Lin
- Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing, 100191, China
| | - Na Lei
- Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing, 100191, China.
| | - Xing Chen
- Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing, 100191, China
| | - Wang Kang
- Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing, 100191, China
| | - Zhiyuan Zhao
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
| | - Dahai Wei
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
| | - Chao Chen
- Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing, 100191, China
| | - Simin Pang
- State Key Laboratory for 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
| | - Linglong Hu
- Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education, Jilin Normal University, Changchun, 130103, China
| | - Liu Yang
- Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing, 100191, China
| | - Enxuan Dong
- Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing, 100191, China
| | - Li Zhao
- The Center for Advanced Quantum Studies and Department of Physics, Beijing Normal University, Beijing, 100875, China
| | - Lei Liu
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
| | - Zhe Yuan
- The Center for Advanced Quantum Studies and Department of Physics, Beijing Normal University, Beijing, 100875, China
| | - Aladin Ullrich
- Institute of Physics, University of Augsburg, Augsburg, 86159, Germany
| | - Christian H Back
- Department of Physics, Technical University of Munich, Garching, 85748, Germany
- Munich Center for Quantum Science and Technology (MCQST), Munich, 80799, Germany
- Centre for Quantum Engineering (ZQE), Technical University of Munich, 85748, Garching, Germany
| | - Jun Zhang
- State Key Laboratory for 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
- CAS Center of Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Dong Pan
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
| | - Jianhua Zhao
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
| | - Ming Feng
- Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education, Jilin Normal University, Changchun, 130103, China.
| | - Albert Fert
- Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing, 100191, China
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, Palaiseau, 91767, France
| | - Weisheng Zhao
- Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing, 100191, China
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9
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Sankhi BR, Echeverria EM, Mandal S, Annaorazov M, Sachan R, Mcllroy DN, Meyers D, Turgut E. Engineering Pt/Co/AlO xheterostructures to enhance the Dzyaloshinskii-Moriya interaction. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2023; 35:145802. [PMID: 36753770 DOI: 10.1088/1361-648x/acba73] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Accepted: 02/08/2023] [Indexed: 06/18/2023]
Abstract
The study of interfacial Dzyaloshinskii-Moriya interaction (DMI) in perpendicularly magnetized structurally asymmetric heavy metal/ferromagnet multilayer systems is of high importance due to the formation of chiral magnetic textures in the presence of DMI. Here, we report the impact of cobalt oxidation at the Co/AlOxinterface in Pt/Co/AlOxtrilayer structures on the DMI by varying the post-growth annealing time, Al thickness and substrate. To quantify DMI we employed magneto-optical imaging of the asymmetric domain wall expansion, hysteresis loop shift, and spin-wave spectroscopy techniques. We further correlated the Co oxidation with low-temperature Hall effect measurements and x-ray photoelectron spectroscopy. Our results emphasize the importance of full characterization of the magnetic films that could be used for magnetic random access memory technologies when subjected to the semiconductor temperature processing conditions, as the magnetic interactions are critical for device performance and can be highly sensitive to oxidation and other effects.
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Affiliation(s)
- Babu R Sankhi
- Department of Physics, Oklahoma State University, Stillwater, OK 74078-3072, United States of America
| | - Elena M Echeverria
- Department of Physics, Oklahoma State University, Stillwater, OK 74078-3072, United States of America
| | - Soumya Mandal
- Department of Mechanical and Aerospace Engineering, Oklahoma State University, Stillwater, OK 74078-3072, United States of America
| | - Muhammet Annaorazov
- Department of Physics, Oklahoma State University, Stillwater, OK 74078-3072, United States of America
| | - Ritesh Sachan
- Department of Mechanical and Aerospace Engineering, Oklahoma State University, Stillwater, OK 74078-3072, United States of America
| | - David N Mcllroy
- Department of Physics, Oklahoma State University, Stillwater, OK 74078-3072, United States of America
| | - Derek Meyers
- Department of Physics, Oklahoma State University, Stillwater, OK 74078-3072, United States of America
| | - Emrah Turgut
- Department of Physics, Oklahoma State University, Stillwater, OK 74078-3072, United States of America
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10
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Makushko P, Kosub T, Pylypovskyi OV, Hedrich N, Li J, Pashkin A, Avdoshenko S, Hübner R, Ganss F, Wolf D, Lubk A, Liedke MO, Butterling M, Wagner A, Wagner K, Shields BJ, Lehmann P, Veremchuk I, Fassbender J, Maletinsky P, Makarov D. Flexomagnetism and vertically graded Néel temperature of antiferromagnetic Cr2O3 thin films. Nat Commun 2022; 13:6745. [DOI: 10.1038/s41467-022-34233-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 10/13/2022] [Indexed: 11/09/2022] Open
Abstract
AbstractAntiferromagnetic insulators are a prospective materials platform for magnonics, spin superfluidity, THz spintronics, and non-volatile data storage. A magnetomechanical coupling in antiferromagnets offers vast advantages in the control and manipulation of the primary order parameter yet remains largely unexplored. Here, we discover a new member in the family of flexoeffects in thin films of Cr2O3. We demonstrate that a gradient of mechanical strain can impact the magnetic phase transition resulting in the distribution of the Néel temperature along the thickness of a 50-nm-thick film. The inhomogeneous reduction of the antiferromagnetic order parameter induces a flexomagnetic coefficient of about 15 μB nm−2. The antiferromagnetic ordering in the inhomogeneously strained films can persist up to 100 °C, rendering Cr2O3 relevant for industrial electronics applications. Strain gradient in Cr2O3 thin films enables fundamental research on magnetomechanics and thermodynamics of antiferromagnetic solitons, spin waves and artificial spin ice systems in magnetic materials with continuously graded parameters.
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11
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Giant stress response of terahertz magnons in a spin-orbit Mott insulator. Nat Commun 2022; 13:6674. [DOI: 10.1038/s41467-022-34375-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 10/21/2022] [Indexed: 11/06/2022] Open
Abstract
AbstractMagnonic devices operating at terahertz frequencies offer intriguing prospects for high-speed electronics with minimal energy dissipation However, guiding and manipulating terahertz magnons via external parameters present formidable challenges. Here we report the results of magnetic Raman scattering experiments on the antiferromagnetic spin-orbit Mott insulator Sr2IrO4 under uniaxial stress. We find that the energies of zone-center magnons are extremely stress sensitive: lattice strain of 0.1% increases the magnon energy by 40%. The magnon response is symmetric with respect to the sign of the applied stress (tensile or compressive), but depends strongly on its direction in the IrO2 planes. A theory based on coupling of the spin-orbit-entangled iridium magnetic moments to lattice distortions provides a quantitative explanation of the Raman data and a comprehensive framework for the description of magnon-lattice interactions in magnets with strong spin-orbit coupling. The possibility to efficiently manipulate the propagation of terahertz magnons via external stress opens up multifold design options for reconfigurable magnonic devices.
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12
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Liu L, Chen W, Zheng Y. Flexoresponses of Synthetic Antiferromagnetic Systems Hosting Skyrmions. PHYSICAL REVIEW LETTERS 2022; 128:257201. [PMID: 35802441 DOI: 10.1103/physrevlett.128.257201] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 06/02/2022] [Indexed: 06/15/2023]
Abstract
While strain gradients break lattice centrosymmetry, ferromagnetism is a time-reversal symmetry breaking product. Flexomagnetic effect in ferromagnets is usually indirect and weak. In this Letter, we reveal a topologically enhanced flexomagnetic effect in synthetic antiferromagnetic systems based on Dzyaloshinskii-Moriya interaction and the large deformability of skyrmion. Moreover, the synthetic antiferromagnetic skyrmion exhibits an unexpected Hall effect under strain gradient. We propose that this flexo-Hall effect originates from a geometric Magnus force related to the asymmetric deformation of skyrmion. Our results shed new insights into the flexoresponses in systems hosting topological structures and may open up a new field-"flexoskyrmionics".
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Affiliation(s)
- Linjie Liu
- Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices, School of Physics, Sun Yat-sen University, Guangzhou 510275, China
- State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics, Sun Yat-sen University, 510275 Guangzhou, China
- Centre for Physical Mechanics and Biophysics, School of Physics, Sun Yat-sen University, 510275 Guangzhou, China
| | - Weijin Chen
- Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices, School of Physics, Sun Yat-sen University, Guangzhou 510275, China
- State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics, Sun Yat-sen University, 510275 Guangzhou, China
- Centre for Physical Mechanics and Biophysics, School of Physics, Sun Yat-sen University, 510275 Guangzhou, China
- School of Materials, Sun Yat-sen University, 518107 Shenzhen, China
| | - Yue Zheng
- Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices, School of Physics, Sun Yat-sen University, Guangzhou 510275, China
- State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics, Sun Yat-sen University, 510275 Guangzhou, China
- Centre for Physical Mechanics and Biophysics, School of Physics, Sun Yat-sen University, 510275 Guangzhou, China
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13
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Wu B, Jin M, Luo Y, Xu X, Fan H, Huang H, Feng Z, Zhuang Y, Yu C, Zhou T. Enhancement of Damping-Like Field and Field-Free Switching in Pt/(Co/Pt)/PtMn Trilayer Films Prepared in the Presence of an In Situ Magnetic Field. ACS APPLIED MATERIALS & INTERFACES 2022; 14:21668-21676. [PMID: 35471960 DOI: 10.1021/acsami.2c02621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The current-induced magnetization switching and damping-like field in Pt/(Co/Pt)/PtMn trilayer films prepared with and without an in situ in-plane field of 600 Oe have been studied systematically. In the presence of the in situ field, a small in-plane bias field (HEB) is observed for films with PtMn thickness ≥5 nm, while there is no observable HEB for PtMn thickness ≤3 nm. Nevertheless, a field-free switching of perpendicular magnetization of Co/Pt is observed for all the films with the PtMn thickness of 1-7 nm. On the other hand, without the presence of the in situ field, HEB and field-free switching are not seen. Furthermore, the damping-like fields (HDL) are much enhanced in the presence of the in situ field, and the increasement can be up to 47%. We further revealed that the spin current is mainly from the Pt layer, while the noncollinear spin configuration at the interface caused by the in situ in-plane field may play a role in the HDL enhancement. Micromagnetic simulations indicate that the canting of antiferromagnet PtMn spins plays an important role in the field-free switching. Our findings clarify the source of spin current in the trilayer films and provide an easier approach to field-free switching and HDL enhancement for future low-power spintronic devices.
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Affiliation(s)
- Birui Wu
- School of Electronics and Information Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang 310018, China
- College of Information and Mechanical Electrical Engineering, Ningde Normal University, Ningde 352100, China
| | - Menghao Jin
- School of Electronics and Information Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang 310018, China
| | - Yongming Luo
- School of Electronics and Information Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang 310018, China
| | - Xiuyuan Xu
- Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool L3 8LG, UK
| | - Haodong Fan
- School of Electronics and Information Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang 310018, China
| | - Haixia Huang
- School of Electronics and Information Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang 310018, China
| | - Zhongshu Feng
- School of Electronics and Information Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang 310018, China
| | - Yanshan Zhuang
- School of Electronics and Information Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang 310018, China
| | - Changqiu Yu
- School of Electronics and Information Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang 310018, China
| | - Tiejun Zhou
- School of Electronics and Information Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang 310018, China
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14
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Jiang L, Huang C, Zhu Y, Pan Y, Fan J, Zhang K, Ma C, Shi D, Zhang H. Tuning the size of skyrmion by strain at the Co/Pt3 Interfaces. iScience 2022; 25:104039. [PMID: 35330683 PMCID: PMC8938285 DOI: 10.1016/j.isci.2022.104039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 02/09/2022] [Accepted: 03/03/2022] [Indexed: 11/25/2022] Open
Abstract
Based on density functional theory calculations, we elucidated the tunability of the atomic structures and magnetic interactions of Co/Pt3 interface (one layer of hcp(0001) Co and three layers of fcc(111) Pt) and thus the skyrmion sizes using strain. The dispersion relations of the spin spiral in the opposite directions, E(q) and E(-q), were evaluated based on generalized Bloch equations. Effective exchange coupling (EC) and Dzyaloshinsky-Moriya interaction (DMI) parameters between different neighbors Ji and di at different lattice constants were derived by fitting the resulting spin spiral dispersion E(q) to EC model with DMI and E(q)-E(-q) formula, respectively. We observed an increase in DMI and a significant decrease in EC with an increase in strain. Hence, the size of Néel-type skyrmions determined by the ratio of EC/DMI can be controlled by applying strain, leading to an effective approach to tailor the formation of skyrmion lattices by inducing slight structural modifications on the magnetic thin films. Calculate the EC and DMI of multi-nearest neighbors in the VASP program Show detailed changes of multi-nearest neighboring EC and DMI with deformation The size of skyrmion does decrease as the lattice constant increases Distance between Co and Pt layer determines the size of DMI
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15
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Zech P, Otto A, Radons G. Dynamics of a driven harmonic oscillator coupled to pairwise interacting Ising spins in random fields. Phys Rev E 2021; 104:054212. [PMID: 34942718 DOI: 10.1103/physreve.104.054212] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 10/25/2021] [Indexed: 11/07/2022]
Abstract
In general we are interested in dynamical systems coupled to complex hysteresis. Therefore as a first step we investigated recently the dynamics of a periodically driven damped harmonic oscillator coupled to independent Ising spins in a random field. Although such a system does not produce hysteresis, we showed how to characterize the dynamics of such a piecewise-smooth system, especially in the case of a large number of spins [Zech, Otto, and Radons, Phys. Rev. E 101, 042217 (2020)2470-004510.1103/PhysRevE.101.042217]. In this paper we extend our model to spin dimers, thus pairwise interacting spins. We show in which cases two interacting spins can show elementary hysteresis, and we give a connection to the Preisach model, which allows us to consider an infinite number of spin pairs. This thermodynamic limit leads us to a dynamical system with an additional hysteretic force in the form of a generalized play operator. By using methods from general chaos theory, piecewise-smooth system theory, and statistics we investigate the chaotic behavior of the dynamical system for a few spins and also in the case of a larger number of spins by calculating bifurcation diagrams, Lyapunov exponents, fractal dimensions, and self-averaging properties. We find that the fractal dimensions and the magnetization are in general not self-averaging quantities. We show how the dynamical properties of the piecewise-smooth system for a large number of spins differs from the system in its thermodynamic limit.
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Affiliation(s)
- Paul Zech
- Institute of Physics, Chemnitz University of Technology, 09107 Chemnitz, Germany
| | - Andreas Otto
- Institute of Physics, Chemnitz University of Technology, 09107 Chemnitz, Germany.,Fraunhofer Institute for Machine Tools and Forming Technology IWU, Reichenhainer Str. 88, 09126 Chemnitz, Germany
| | - Günter Radons
- Institute of Physics, Chemnitz University of Technology, 09107 Chemnitz, Germany.,Institute of Mechatronics, Reichenhainer Str. 88, 09126 Chemnitz, Germany
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16
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Topological spin/structure couplings in layered chiral magnet Cr 1/3TaS 2: The discovery of spiral magnetic superstructure. Proc Natl Acad Sci U S A 2021; 118:2023337118. [PMID: 34593631 DOI: 10.1073/pnas.2023337118] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/30/2021] [Indexed: 11/18/2022] Open
Abstract
Chiral magnets have recently emerged as hosts for topological spin textures and related transport phenomena, which can find use in next-generation spintronic devices. The coupling between structural chirality and noncollinear magnetism is crucial for the stabilization of complex spin structures such as magnetic skyrmions. Most studies have been focused on the physical properties in homochiral states favored by crystal growth and the absence of long-ranged interactions between domains of opposite chirality. Therefore, effects of the high density of chiral domains and domain boundaries on magnetic states have been rarely explored so far. Herein, we report layered heterochiral Cr1/3TaS2, exhibiting numerous chiral domains forming topological defects and a nanometer-scale helimagnetic order interlocked with the structural chirality. Tuning the chiral domain density, we discovered a macroscopic topological magnetic texture inside each chiral domain that has an appearance of a spiral magnetic superstructure composed of quasiperiodic Néel domain walls. The spirality of this object can have either sign and is decoupled from the structural chirality. In weak, in-plane magnetic fields, it transforms into a nonspiral array of concentric ring domains. Numerical simulations suggest that this magnetic superstructure is stabilized by strains in the heterochiral state favoring noncollinear spins. Our results unveil topological structure/spin couplings in a wide range of different length scales and highly tunable spin textures in heterochiral magnets.
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17
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Franke KJA, Ophus C, Schmid AK, Marrows CH. Switching between Magnetic Bloch and Néel Domain Walls with Anisotropy Modulations. PHYSICAL REVIEW LETTERS 2021; 127:127203. [PMID: 34597075 DOI: 10.1103/physrevlett.127.127203] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 07/08/2021] [Accepted: 08/09/2021] [Indexed: 06/13/2023]
Abstract
It has been shown previously that the presence of a Dzyaloshinskii-Moriya interaction in perpendicularly magnetized thin films stabilizes Néel type domain walls. We demonstrate, using micromagnetic simulations and analytical modeling, that the presence of a uniaxial in plane magnetic anisotropy can also lead to the formation of Néel walls in the absence of a Dzyaloshinskii-Moriya interaction. It is possible to abruptly switch between Bloch and Néel walls via a small modulation of the in plane, but also the perpendicular, magnetic anisotropy. This opens up a route toward electric field control of the domain wall type with small applied voltages through electric field controlled anisotropies.
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Affiliation(s)
- Kévin J A Franke
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Colin Ophus
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Andreas K Schmid
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
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18
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Barman A, Gubbiotti G, Ladak S, Adeyeye AO, Krawczyk M, Gräfe J, Adelmann C, Cotofana S, Naeemi A, Vasyuchka VI, Hillebrands B, Nikitov SA, Yu H, Grundler D, Sadovnikov AV, Grachev AA, Sheshukova SE, Duquesne JY, Marangolo M, Csaba G, Porod W, Demidov VE, Urazhdin S, Demokritov SO, Albisetti E, Petti D, Bertacco R, Schultheiss H, Kruglyak VV, Poimanov VD, Sahoo S, Sinha J, Yang H, Münzenberg M, Moriyama T, Mizukami S, Landeros P, Gallardo RA, Carlotti G, Kim JV, Stamps RL, Camley RE, Rana B, Otani Y, Yu W, Yu T, Bauer GEW, Back C, Uhrig GS, Dobrovolskiy OV, Budinska B, Qin H, van Dijken S, Chumak AV, Khitun A, Nikonov DE, Young IA, Zingsem BW, Winklhofer M. The 2021 Magnonics Roadmap. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:413001. [PMID: 33662946 DOI: 10.1088/1361-648x/abec1a] [Citation(s) in RCA: 68] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 03/04/2021] [Indexed: 05/26/2023]
Abstract
Magnonics is a budding research field in nanomagnetism and nanoscience that addresses the use of spin waves (magnons) to transmit, store, and process information. The rapid advancements of this field during last one decade in terms of upsurge in research papers, review articles, citations, proposals of devices as well as introduction of new sub-topics prompted us to present the first roadmap on magnonics. This is a collection of 22 sections written by leading experts in this field who review and discuss the current status besides presenting their vision of future perspectives. Today, the principal challenges in applied magnonics are the excitation of sub-100 nm wavelength magnons, their manipulation on the nanoscale and the creation of sub-micrometre devices using low-Gilbert damping magnetic materials and its interconnections to standard electronics. To this end, magnonics offers lower energy consumption, easier integrability and compatibility with CMOS structure, reprogrammability, shorter wavelength, smaller device features, anisotropic properties, negative group velocity, non-reciprocity and efficient tunability by various external stimuli to name a few. Hence, despite being a young research field, magnonics has come a long way since its early inception. This roadmap asserts a milestone for future emerging research directions in magnonics, and hopefully, it will inspire a series of exciting new articles on the same topic in the coming years.
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Affiliation(s)
- Anjan Barman
- Department of Condensed Matter Physics and Material Sciences, S N Bose National Centre for Basic Sciences, Salt Lake, Kolkata 700106, India
| | - Gianluca Gubbiotti
- Istituto Officina dei Materiali del Consiglio nazionale delle Ricerche (IOM-CNR), Perugia, Italy
| | - S Ladak
- School of Physics and Astronomy, Cardiff University, United Kingdom
| | - A O Adeyeye
- Department of Physics, University of Durham, United Kingdom
| | - M Krawczyk
- Adam Mickiewicz University, Poznan, Poland
| | - J Gräfe
- Max Planck Institute for Intelligent Systems, Stuttgart, Germany
| | | | - S Cotofana
- Delft University of Technology, The Netherlands
| | - A Naeemi
- Georgia Institute of Technology, United States of America
| | - V I Vasyuchka
- Department of Physics and State Research Center OPTIMAS, Technische Universität Kaiserslautern (TUK), Kaiserslautern, Germany
| | - B Hillebrands
- Department of Physics and State Research Center OPTIMAS, Technische Universität Kaiserslautern (TUK), Kaiserslautern, Germany
| | - S A Nikitov
- Kotelnikov Institute of Radioengineering and Electronics, Moscow, Russia
| | - H Yu
- Fert Beijing Institute, BDBC, School of Microelectronics, Beijing Advanced Innovation Center for Big Data and Brian Computing, Beihang University, People's Republic of China
| | - D Grundler
- Laboratory of Nanoscale Magnetic Materials and Magnonics, Institute of Materials (IMX), Institute of Electrical and Micro Engineering, School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Switzerland
| | - A V Sadovnikov
- Kotelnikov Institute of Radioengineering and Electronics, Moscow, Russia
- Laboratory 'Magnetic Metamaterials', Saratov State University, Saratov, Russia
| | - A A Grachev
- Kotelnikov Institute of Radioengineering and Electronics, Moscow, Russia
- Laboratory 'Magnetic Metamaterials', Saratov State University, Saratov, Russia
| | - S E Sheshukova
- Kotelnikov Institute of Radioengineering and Electronics, Moscow, Russia
- Laboratory 'Magnetic Metamaterials', Saratov State University, Saratov, Russia
| | - J-Y Duquesne
- Institut des NanoSciences de Paris, Sorbonne University, CNRS, Paris, France
| | - M Marangolo
- Institut des NanoSciences de Paris, Sorbonne University, CNRS, Paris, France
| | - G Csaba
- Pázmány University, Budapest, Hungary
| | - W Porod
- University of Notre Dame, IN, United States of America
| | - V E Demidov
- Institute for Applied Physics, University of Muenster, Muenster, Germany
| | - S Urazhdin
- Department of Physics, Emory University, Atlanta, United States of America
| | - S O Demokritov
- Institute for Applied Physics, University of Muenster, Muenster, Germany
| | | | - D Petti
- Polytechnic University of Milan, Italy
| | | | - H Schultheiss
- Helmholtz-Center Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, Germany
- Technische Universität Dresden, Germany
| | | | | | - S Sahoo
- Department of Condensed Matter Physics and Material Sciences, S N Bose National Centre for Basic Sciences, Salt Lake, Kolkata 700106, India
| | - J Sinha
- Department of Physics and Nanotechnology, SRM Institute of Science and Technology, Kattankulathur, India
| | - H Yang
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore
| | - M Münzenberg
- Institute of Physics, University of Greifswald, Greifswald, Germany
| | - T Moriyama
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto, Japan
- Centre for Spintronics Research Network, Japan
| | - S Mizukami
- Centre for Spintronics Research Network, Japan
- Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, Sendai, Japan
| | - P Landeros
- Departamento de Física, Universidad Técnica Federico Santa María, Valparaíso, Chile
- Center for the Development of Nanoscience and Nanotechnology (CEDENNA), Santiago, Chile
| | - R A Gallardo
- Departamento de Física, Universidad Técnica Federico Santa María, Valparaíso, Chile
- Center for the Development of Nanoscience and Nanotechnology (CEDENNA), Santiago, Chile
| | - G Carlotti
- Dipartimento di Fisica e Geologia, University of Perugia, Perugia, Italy
- CNR Instituto Nanoscienze, Modena, Italy
| | - J-V Kim
- Centre for Nanosciences and Nanotechnology, CNRS, Université Paris-Saclay, Palaiseau, France
| | - R L Stamps
- Department of Physics and Astronomy, University of Manitoba, Canada
| | - R E Camley
- Center for Magnetism and Magnetic Nanostructures, University of Colorado, Colorado Springs, United States of America
| | | | - Y Otani
- RIKEN, Japan
- Institute for Solid State Physics (ISSP), University of Tokyo, Japan
| | - W Yu
- Institute for Materials Research, Tohoku University, Sendai, 980-8577, Japan
| | - T Yu
- Max Planck Institute for the Structure and Dynamics of Matter, Hamburg, Germany
| | - G E W Bauer
- Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, Sendai, Japan
- Zernike Institute for Advanced Materials, Groningen University, The Netherlands
| | - C Back
- Technical University Munich, Germany
| | - G S Uhrig
- Technical University Dortmund, Germany
| | | | - B Budinska
- Faculty of Physics, University of Vienna, Vienna, Austria
| | - H Qin
- Department of Applied Physics, School of Science, Aalto University, Finland
| | - S van Dijken
- Department of Applied Physics, School of Science, Aalto University, Finland
| | - A V Chumak
- Faculty of Physics, University of Vienna, Vienna, Austria
| | - A Khitun
- University of California Riverside, United States of America
| | - D E Nikonov
- Components Research, Intel, Hillsboro, Oregon, United States of America
| | - I A Young
- Components Research, Intel, Hillsboro, Oregon, United States of America
| | - B W Zingsem
- The University of Duisburg-Essen, CENIDE, Germany
| | - M Winklhofer
- The Carl von Ossietzky University of Oldenburg, Germany
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19
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Adhikari A, Gilroy ER, Hayward TJ, Adenwalla S. Surface acoustic wave assisted depinning of magnetic domain walls. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:31LT01. [PMID: 34010816 DOI: 10.1088/1361-648x/ac02e4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 05/19/2021] [Indexed: 06/12/2023]
Abstract
We investigate the effects of high frequency strain on the depinning of magnetic domain walls in perpendicular anisotropy materials. Micron wide stripes of [Co(0.3 nm)/Pt(0.6 nm)]5are patterned between a pair of identical inter-digital transducers that generate high frequency (114.8 MHz) standing surface acoustic waves. We use magneto-optical Kerr effect microscopy to characterize the thermally-assisted depinning of domain walls at defect sites within the strips. Our results show that the excitation of the domain walls with surface acoustic waves results in an increase in their depinning probabilities by approximately a factor of 10. Our data are consistent with a model in which the magnetoelastic anisotropies induced by the acoustic waves modulate the energy barriers that pin the domain walls. These results suggest an alternative route to domain wall depinning in thin films and nanostructures and are relevant to the development of racetrack memories, where domain wall pinning can result in reduced velocities and non-deterministic motion.
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Affiliation(s)
- A Adhikari
- Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, NE 68588, United States of America
| | - E R Gilroy
- Department of Materials Science and Engineering, University of Sheffield, Sheffield, United Kingdom
| | - T J Hayward
- Department of Materials Science and Engineering, University of Sheffield, Sheffield, United Kingdom
| | - S Adenwalla
- Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, NE 68588, United States of America
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20
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Zhang W, Chen R, Jiang B, Zhao X, Zhao W, Yan SS, Han G, Yu S, Liu G, Kang S. Tunable interfacial Dzyaloshinskii-Moriya interaction in symmetrical Au/[Fe/Au] n multilayers. NANOSCALE 2021; 13:2665-2672. [PMID: 33496295 DOI: 10.1039/d0nr06488b] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The interfacial Dzyaloshinskii-Moriya interaction (i-DMI) has been exploited in as-made symmetrical Au/[Fe/Au]n structures. By tailoring the chirality of the i-DMI at the Au/Fe interface, an overall enhancement of the i-DMI can be obtained in such a symmetrical structure. Furthermore, the tunability of the i-DMI was realized by changing the stacking number n. Compared to the top of Fe, a large tensile stress at the bottom of Fe due to lattice mismatch was responsible for the chirality change in the sub/Au/Fe system. Layer-resolved DMI calculations revealed that the sign of the spin-orbit coupling (SOC) energy was changed for Au near the interface of Au/Fe under tensile stress, subsequently reversing the chirality of the i-DMI from left-handed to right-handed. Our findings provide a simplest way to tune the i-DMI in a multilayer system, further benefiting the application of skyrmion-based devices.
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Affiliation(s)
- W Zhang
- School of Physics, State Key Laboratory of Crystal Material, Shandong University, Jinan 250100, China.
| | - R Chen
- Fert Beijing Institute, School of Microelectronics, Beijing Advanced Innovation Center for Big Data and Brain Computing, Beihang University, Beijing 100191, China
| | - B Jiang
- School of Physics, State Key Laboratory of Crystal Material, Shandong University, Jinan 250100, China.
| | - X Zhao
- School of Physics, State Key Laboratory of Crystal Material, Shandong University, Jinan 250100, China.
| | - W Zhao
- Fert Beijing Institute, School of Microelectronics, Beijing Advanced Innovation Center for Big Data and Brain Computing, Beihang University, Beijing 100191, China
| | - S S Yan
- School of Physics, State Key Laboratory of Crystal Material, Shandong University, Jinan 250100, China.
| | - G Han
- School of Physics, State Key Laboratory of Crystal Material, Shandong University, Jinan 250100, China.
| | - S Yu
- School of Physics, State Key Laboratory of Crystal Material, Shandong University, Jinan 250100, China.
| | - G Liu
- School of Physics, State Key Laboratory of Crystal Material, Shandong University, Jinan 250100, China.
| | - S Kang
- School of Physics, State Key Laboratory of Crystal Material, Shandong University, Jinan 250100, China.
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21
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Wang Y, Wang L, Xia J, Lai Z, Tian G, Zhang X, Hou Z, Gao X, Mi W, Feng C, Zeng M, Zhou G, Yu G, Wu G, Zhou Y, Wang W, Zhang XX, Liu J. Electric-field-driven non-volatile multi-state switching of individual skyrmions in a multiferroic heterostructure. Nat Commun 2020; 11:3577. [PMID: 32681004 PMCID: PMC7367868 DOI: 10.1038/s41467-020-17354-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Accepted: 06/26/2020] [Indexed: 11/09/2022] Open
Abstract
Electrical manipulation of skyrmions attracts considerable attention for its rich physics and promising applications. To date, such a manipulation is realized mainly via spin-polarized current based on spin-transfer torque or spin-orbital torque effect. However, this scheme is energy consuming and may produce massive Joule heating. To reduce energy dissipation and risk of heightened temperatures of skyrmion-based devices, an effective solution is to use electric field instead of current as stimulus. Here, we realize an electric-field manipulation of skyrmions in a nanostructured ferromagnetic/ferroelectrical heterostructure at room temperature via an inverse magneto-mechanical effect. Intriguingly, such a manipulation is non-volatile and exhibits a multistate feature. Numerical simulations indicate that the electric-field manipulation of skyrmions originates from strain-mediated modification of effective magnetic anisotropy and Dzyaloshinskii-Moriya interaction. Our results open a direction for constructing low-energy-dissipation, non-volatile, and multistate skyrmion-based spintronic devices.
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Affiliation(s)
- Yadong Wang
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology & Institute for Advanced Materials, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou, 510006, China
- National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou, 510006, China
| | - Lei Wang
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Jing Xia
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong, 518172, China
| | - Zhengxun Lai
- Colleage of Science, Tianjin University, Tianjin, 300392, China
| | - Guo Tian
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology & Institute for Advanced Materials, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou, 510006, China
- National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou, 510006, China
| | - Xichao Zhang
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong, 518172, China
| | - Zhipeng Hou
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology & Institute for Advanced Materials, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou, 510006, China.
- National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou, 510006, China.
| | - Xingsen Gao
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology & Institute for Advanced Materials, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou, 510006, China.
- National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou, 510006, China.
| | - Wenbo Mi
- Colleage of Science, Tianjin University, Tianjin, 300392, China
| | - Chun Feng
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, China.
| | - Min Zeng
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology & Institute for Advanced Materials, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou, 510006, China
- National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou, 510006, China
| | - Guofu Zhou
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology & Institute for Advanced Materials, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou, 510006, China
- National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou, 510006, China
| | - Guanghua Yu
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Guangheng Wu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Yan Zhou
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong, 518172, China
| | - Wenhong Wang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Xi-Xiang Zhang
- Physical Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Junming Liu
- Laboratory of Solid State Microstructures and Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 211102, China
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22
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Zhou H, Yu F, Jiang X, Lu C, Cao Z, Chen X, Gao H, Yang A. Analysis of Magneto-Mechanical Response for Magnetization-Graded Ferromagnetic Material in Magnetoelectric Laminate. MATERIALS 2020; 13:ma13122812. [PMID: 32580483 PMCID: PMC7344662 DOI: 10.3390/ma13122812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 06/14/2020] [Accepted: 06/15/2020] [Indexed: 11/18/2022]
Abstract
This paper analyzes the dynamic magneto-mechanical response in magnetization-graded ferromagnetic materials (MGFM) comprised of high-permeability Finemet and traditional magnetostrictive materials. The theoretical modeling of the piezomagnetic coefficient that depends on the bias magnetic field of MGFM is proposed by using the nonlinear constitutive model of a piezomagnetic material, the magnetoelectric equivalent circuit method, and the simulation software Ansoft. The theoretical variation of piezomagnetic coefficients of MGFM on the bias magnetic field is in good agreement with the experiment. Using the piezomagnetic coefficient in the magnetoelectric voltage model, the theoretical longitudinal resonant magnetoelectric voltage coefficients have also been calculated, which are consistent with the experimental values. This theoretical analysis is beneficial to comprehensively understand the self-biased piezomagnetic response of MGFM, and to design magnetoelectric devices with MGFM.
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Affiliation(s)
- Hai Zhou
- Department of Electromechanical Measuring and Controlling, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, China; (H.Z.); (F.Y.); (X.J.); (Z.C.); (X.C.); (H.G.)
| | - Feihu Yu
- Department of Electromechanical Measuring and Controlling, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, China; (H.Z.); (F.Y.); (X.J.); (Z.C.); (X.C.); (H.G.)
| | - Xueling Jiang
- Department of Electromechanical Measuring and Controlling, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, China; (H.Z.); (F.Y.); (X.J.); (Z.C.); (X.C.); (H.G.)
| | - Caijiang Lu
- Department of Electromechanical Measuring and Controlling, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, China; (H.Z.); (F.Y.); (X.J.); (Z.C.); (X.C.); (H.G.)
- Correspondence: or
| | - Zhongqing Cao
- Department of Electromechanical Measuring and Controlling, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, China; (H.Z.); (F.Y.); (X.J.); (Z.C.); (X.C.); (H.G.)
| | - Xiang Chen
- Department of Electromechanical Measuring and Controlling, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, China; (H.Z.); (F.Y.); (X.J.); (Z.C.); (X.C.); (H.G.)
| | - Hongli Gao
- Department of Electromechanical Measuring and Controlling, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, China; (H.Z.); (F.Y.); (X.J.); (Z.C.); (X.C.); (H.G.)
| | - Aichao Yang
- Jiangxi Electric Power Research Institute, Nanchang 330096, China;
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