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Grochot K, Ogrodnik P, Mojsiejuk J, Mazalski P, Guzowska U, Skowroński W, Stobiecki T. Influence of ferromagnetic interlayer exchange coupling on current-induced magnetization switching and Dzyaloshinskii-Moriya interaction in Co/Pt/Co multilayer system. Sci Rep 2024; 14:9938. [PMID: 38688928 PMCID: PMC11061319 DOI: 10.1038/s41598-024-60492-x] [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: 12/29/2023] [Accepted: 04/23/2024] [Indexed: 05/02/2024] Open
Abstract
This paper investigates the relationship among interlayer exchange coupling (IEC), Dzyaloshinskii-Moriya interaction (DMI), and multilevel magnetization switching within a Co/Pt/Co heterostructure, where varying Pt thicknesses enable control over the coupling strength. Employing Brillouin Light Scattering to quantify the effective DMI, we explore its potential role in magnetization dynamics and multilevel magnetization switching. Experimental findings show four distinct resistance states under an external magnetic field and spin Hall effect related spin current. We explain this phenomenon based on the asymmetry between Pt/Co and Co/Pt interfaces and the interlayer coupling, which, in turn, influences the DMI and subsequently impacts the magnetization dynamics. Numerical simulations, including macrospin, 1D domain wall, and simple spin wave models, further support the experimental observations of multilevel switching and help uncover the underlying mechanisms. Our proposed explanation, supported by magnetic domain observation using polar-magnetooptical Kerr microscopy, offers insights into both the spatial distribution of magnetization and its dynamics for different IECs, thereby shedding light on its interplay with DMI, which may lead to potential applications in storage devices.
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Affiliation(s)
- Krzysztof Grochot
- Institute of Electronics, AGH University of Krakow, Krakow, Poland.
- Faculty of Physics and Computer Science, AGH University of Krakow, Krakow, Poland.
| | - Piotr Ogrodnik
- Faculty of Physics, Warsaw University of Technology, Warsaw, Poland.
| | - Jakub Mojsiejuk
- Institute of Electronics, AGH University of Krakow, Krakow, Poland
| | - Piotr Mazalski
- Faculty of Physics, University of Bialystok, Bialystok, Poland
| | | | | | - Tomasz Stobiecki
- Institute of Electronics, AGH University of Krakow, Krakow, Poland
- Faculty of Physics and Computer Science, AGH University of Krakow, Krakow, Poland
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2
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Li W, Zhu W, Zhang G, Wu H, Zhu S, Li R, Zhang E, Zhang X, Deng Y, Zhang J, Zhao L, Chang H, Wang K. Room-Temperature van der Waals Ferromagnet Switching by Spin-Orbit Torques. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2303688. [PMID: 37890473 DOI: 10.1002/adma.202303688] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 10/12/2023] [Indexed: 10/29/2023]
Abstract
The emerging wide varieties of the van der Waals (vdW) magnets with atomically thin and smooth interfaces hold great promise for next-generation spintronic devices. However, due to the lower Curie temperature of the vdW ferromagnets than room temperature, electrically manipulating its magnetization at room temperature has not been realized. In this work, it is demonstrated that the perpendicular magnetization of the vdW ferromagnet Fe3 GaTe2 can be effectively switched at room temperature in the Fe3 GaTe2 /Pt bilayer by spin-orbit torques (SOTs) with a relatively low current density of 1.3 × 107 A cm-2 . Moreover, the high SOT efficiency of ξDL ≈ 0.28 is quantitatively determined by harmonic measurements, which is higher than those in Pt-based heavy metal/conventional ferromagnet devices. The findings of room-temperature vdW ferromagnet switching by SOTs provide a significant basis for the development of vdW-ferromagnet-based spintronic applications.
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Affiliation(s)
- Weihao Li
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wenkai Zhu
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Gaojie Zhang
- Center for Joining and Electronic Packaging, State Key Laboratory of Material Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
- Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Hao Wu
- Center for Joining and Electronic Packaging, State Key Laboratory of Material Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
- Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Shouguo Zhu
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Runze Li
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Enze Zhang
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiaomin Zhang
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yongcheng Deng
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jing Zhang
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
| | - Lixia Zhao
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
- School of Electrical and Electronic Engineering, Tiangong University, Tianjin, 300387, China
| | - Haixin Chang
- Center for Joining and Electronic Packaging, State Key Laboratory of Material Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
- Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Kaiyou Wang
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
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Abstract
Science, engineering, and medicine ultimately demand fast information processing with ultra-low power consumption. The recently developed spin-orbit torque (SOT)-induced magnetization switching paradigm has been fueling opportunities for spin-orbitronic devices, i.e., enabling SOT memory and logic devices at sub-nano second and sub-picojoule regimes. Importantly, spin-orbitronic devices are intrinsic of nonvolatility, anti-radiation, unlimited endurance, excellent stability, and CMOS compatibility, toward emerging applications, e.g., processing in-memory, neuromorphic computing, probabilistic computing, and 3D magnetic random access memory. Nevertheless, the cutting-edge SOT-based devices and application remain at a premature stage owing to the lack of scalable methodology on the field-free SOT switching. Moreover, spin-orbitronics poises as an interdisciplinary field to be driven by goals of both fundamental discoveries and application innovations, to open fascinating new paths for basic research and new line of technologies. In this perspective, the specific challenges and opportunities are summarized to exert momentum on both research and eventual applications of spin-orbitronic devices.
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Affiliation(s)
- Yi Cao
- Beijing Academy of Quantum Information Sciences, Beijing 100193, P. R. China
| | - Guozhong Xing
- Key Laboratory of Microelectronic Devices & Integrated Technology, Institute of Microelectronics, Chinese Academy of Sciences, Beijing 100029, P. R. China
| | - Huai Lin
- Key Laboratory of Microelectronic Devices & Integrated Technology, Institute of Microelectronics, Chinese Academy of Sciences, Beijing 100029, P. R. China
| | - Nan Zhang
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, P. R. China
| | - Houzhi Zheng
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, P. R. China
| | - Kaiyou Wang
- Beijing Academy of Quantum Information Sciences, Beijing 100193, P. R. China
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, P. R. China
- Corresponding author
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Cao Y, Sheng Y, Edmonds KW, Ji Y, Zheng H, Wang K. Deterministic Magnetization Switching Using Lateral Spin-Orbit Torque. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e1907929. [PMID: 32108384 DOI: 10.1002/adma.201907929] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 02/08/2020] [Indexed: 06/10/2023]
Abstract
Current-induced magnetization switching by spin-orbit torque (SOT) holds considerable promise for next generation ultralow-power memory and logic applications. In most cases, generation of spin-orbit torques has relied on an external injection of out-of-plane spin currents into the magnetic layer, while an external magnetic field along the electric current direction is generally required for realizing deterministic switching by SOT. Here, deterministic current-induced SOT full magnetization switching by lateral spin-orbit torque in zero external magnetic field is reported. The Pt/Co/Pt magnetic structure is locally annealed by a laser track along the in-plane current direction, resulting in a lateral Pt gradient within the ferromagnetic layer, as confirmed by microstructure and chemical composition analysis. In zero magnetic field, the direction of the deterministic current-induced magnetization switching depends on the location of the laser track, but shows no dependence on the net polarization of external out-of-plane spin currents. From the behavior under external magnetic fields, two independent mechanisms giving rise to SOT are identified, i.e., the lateral Pt-Co asymmetry as well as out-of-plane injected spin currents, where the polarization and the magnitude of the SOT in the former case depends on the relative location and the laser power of the annealing track.
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Affiliation(s)
- Yi Cao
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
- Beijing Academy of Quantum Information Sciences, Beijing, 100193, China
| | - Yu Sheng
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
| | | | - Yang Ji
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
- Center of Materials Science and Optoelectronic Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Houzhi Zheng
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
- Center of Materials Science and Optoelectronic Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Kaiyou Wang
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
- Beijing Academy of Quantum Information Sciences, Beijing, 100193, China
- Center of Materials Science and Optoelectronic Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
- Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing, 100049, China
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Yu Z, Chen J, Zhang L, Xing Y, Wang J. Magnetization dynamics induced by the Rashba effect in ferromagnetic films. NANOSCALE 2018; 10:18728-18733. [PMID: 30270363 DOI: 10.1039/c8nr04628j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Manipulating the magnetization of ferromagnets by the current-induced spin-orbit torque has great potential application in the design of low energy consumption spintronic devices. Normally, an external magnetic field is needed for the reversal of current assisted magnetization by the spin-orbit torque. Recently, the switching of magnetization driven by the spin-orbit torque in the absence of an external magnetic field was reported in a Ta/Co20Fe60B20/TaOx system with lateral structural asymmetry. To understand the physics behind this experiment, we performed first principles calculations on the potential profile at the interface between the ferromagnetic film and the wedge-shaped deposited metal oxide in the Ta/Co/TaO system. This revealed that the lateral structural asymmetry generates two additional Rashba interactions which can reduce the minimum external field required to reverse the magnetization. In addition, we derived the Landau-Lifshitz-Gilbert equation from a quantum transport perspective and numerically investigated the magnetization dynamics in ferromagnetic films induced by Rashba interactions including those generated by lateral asymmetry. Our theoretical simulation provides microscopic explanations of experimental observations of magnetization switching in the absence of an external field of devices with lateral structural asymmetry.
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Affiliation(s)
- Zhizhou Yu
- Center for Quantum Transport and Thermal Energy Science, School of Physics and Technology, Nanjing Normal University, Nanjing 210023, China
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6
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Qiu X, Shi Z, Fan W, Zhou S, Yang H. Characterization and Manipulation of Spin Orbit Torque in Magnetic Heterostructures. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1705699. [PMID: 29468735 DOI: 10.1002/adma.201705699] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Revised: 11/01/2017] [Indexed: 06/08/2023]
Abstract
Electrical-current-induced magnetization switching is a keystone concept in the development of spintronics devices. In the last few years, this field has experienced a significant boost with the discovery of spin orbit torque (SOT) in magnetic heterostructures. Here, the recent results as to the characterization and manipulation of SOT in various heavy-metal/ferromagnet heterostructures are summarized. First, different electrical measurement methods that allow the physical features of SOT to be revealed are introduced. Second, it is shown that SOT in magnetic heterostructures can be manipulated via various material engineering approaches. The interfacial and bulk contributions of SOT are also discussed. These results advance the understanding of SOT and provide novel approaches toward energy-efficient spintronic devices.
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Affiliation(s)
- Xuepeng Qiu
- Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology and School of Physics Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Zhong Shi
- Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology and School of Physics Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Weijia Fan
- Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology and School of Physics Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Shiming Zhou
- Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology and School of Physics Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Hyunsoo Yang
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117576, Singapore
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7
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Kwak WY, Kwon JH, Grünberg P, Han SH, Cho BK. Current-induced magnetic switching with spin-orbit torque in an interlayer-coupled junction with a Ta spacer layer. Sci Rep 2018; 8:3826. [PMID: 29491458 PMCID: PMC5830507 DOI: 10.1038/s41598-018-22122-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 02/14/2018] [Indexed: 11/09/2022] Open
Abstract
Spin-orbit torque has attracted considerable attention as a means to overcome limits of devices based on spin-transfer torque. However, a small magnetic field that is collinear to the current flow must be applied to break symmetry and induce deterministic current-induced magnetization switching. Recently, a junction utilizing interlayer coupling mediated by a Ru spacer layer between two CoFe layers was designed for symmetry breaking and exhibited current-induced magnetization switching without a magnetic field. Here, we demonstrate zero-field current-induced switching of the perpendicular magnetization of a Co layer that is indirectly coupled with a CoFe layer via a Ta spacer. The weak interlayer coupling exhibited by Ta allows the layer thickness to be relatively small (≈0.5 nm), enabling appropriate interlayer coupling to induce spin-orbit torque for current-induced magnetic switching. External magnetic field effects on switching characteristics show that the current switching process is quite stable against external environments.
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Affiliation(s)
- W-Y Kwak
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
| | - J-H Kwon
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
| | - P Grünberg
- Grünberg Center for Magnetic Nanomaterials, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
| | - S H Han
- Division of Navigation Science, Mokpo National Maritime University, Mokpo, 58628, Republic of Korea
| | - B K Cho
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea. .,Grünberg Center for Magnetic Nanomaterials, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea.
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8
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Spin orbit torques induced magnetization reversal through asymmetric domain wall propagation in Ta/CoFeB/MgO structures. Sci Rep 2018; 8:1355. [PMID: 29358598 PMCID: PMC5777997 DOI: 10.1038/s41598-018-19927-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 01/09/2018] [Indexed: 11/08/2022] Open
Abstract
The magnetization reversal induced by spin orbit torques in the presence of Dzyaloshinskii-Moriya interaction (DMI) in perpendicularly magnetized Ta/CoFeB/MgO structures were investigated by using a combination of Anomalous Hall effect measurement and Kerr effect microscopy techniques. By analyzing the in-plane field dependent spin torque efficiency measurements, an effective field value for the DMI of ~300 Oe was obtained, which plays a key role to stabilize Néel walls in the film stack. Kerr imaging reveals that the current-induced reversal under small and medium in-plane field was mediated by domain nucleation at the edge of the Hall bar, followed by asymmetric domain wall (DW) propagation. However, as the in-plane field strength increases, an isotropic DW expansion was observed before reaching complete reversal. Micromagnetic simulations of the DW structure in the CoFeB layer suggest that the DW configuration under the combined effect of the DMI and the external field is responsible for the various DW propagation behaviors.
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10
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Cai K, Yang M, Ju H, Wang S, Ji Y, Li B, Edmonds KW, Sheng Y, Zhang B, Zhang N, Liu S, Zheng H, Wang K. Electric field control of deterministic current-induced magnetization switching in a hybrid ferromagnetic/ferroelectric structure. NATURE MATERIALS 2017; 16:712-716. [PMID: 28369053 DOI: 10.1038/nmat4886] [Citation(s) in RCA: 118] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 03/01/2017] [Indexed: 05/22/2023]
Abstract
All-electrical and programmable manipulations of ferromagnetic bits are highly pursued for the aim of high integration and low energy consumption in modern information technology. Methods based on the spin-orbit torque switching in heavy metal/ferromagnet structures have been proposed with magnetic field, and are heading toward deterministic switching without external magnetic field. Here we demonstrate that an in-plane effective magnetic field can be induced by an electric field without breaking the symmetry of the structure of the thin film, and realize the deterministic magnetization switching in a hybrid ferromagnetic/ferroelectric structure with Pt/Co/Ni/Co/Pt layers on PMN-PT substrate. The effective magnetic field can be reversed by changing the direction of the applied electric field on the PMN-PT substrate, which fully replaces the controllability function of the external magnetic field. The electric field is found to generate an additional spin-orbit torque on the CoNiCo magnets, which is confirmed by macrospin calculations and micromagnetic simulations.
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Affiliation(s)
- Kaiming Cai
- SKLSM, Institute of Semiconductors, CAS, PO Box 912, Beijing 100083, China
| | - Meiyin Yang
- SKLSM, Institute of Semiconductors, CAS, PO Box 912, Beijing 100083, China
| | - Hailang Ju
- Department of Physics, School of Sciences, Beijing Technology and Business University, Beijing 100048, China
| | - Sumei Wang
- ICAC, Institute of Microelectronics of CAS, University of Chinese Academy of Sciences, Beijing 100029, China
| | - Yang Ji
- SKLSM, Institute of Semiconductors, CAS, PO Box 912, Beijing 100083, China
| | - Baohe Li
- Department of Physics, School of Sciences, Beijing Technology and Business University, Beijing 100048, China
| | | | - Yu Sheng
- SKLSM, Institute of Semiconductors, CAS, PO Box 912, Beijing 100083, China
| | - Bao Zhang
- SKLSM, Institute of Semiconductors, CAS, PO Box 912, Beijing 100083, China
| | - Nan Zhang
- SKLSM, Institute of Semiconductors, CAS, PO Box 912, Beijing 100083, China
| | - Shuai Liu
- Department of Physics, School of Sciences, Beijing Technology and Business University, Beijing 100048, China
| | - Houzhi Zheng
- SKLSM, Institute of Semiconductors, CAS, PO Box 912, Beijing 100083, China
| | - Kaiyou Wang
- SKLSM, Institute of Semiconductors, CAS, PO Box 912, Beijing 100083, China
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Modulated switching current density and spin-orbit torques in MnGa/Ta films with inserting ferromagnetic layers. Sci Rep 2016; 6:38375. [PMID: 27910938 PMCID: PMC5133548 DOI: 10.1038/srep38375] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 11/08/2016] [Indexed: 11/09/2022] Open
Abstract
We report modulated switching current density and spin-orbit torques (SOT) in MnGa/Ta films with inserting very thin Co2FeAl and Co layers. Ferromagnetic coupling has been found in MnGa/Co2FeAl/Ta, resulting in a decreased effective anisotropy field. On the contrary, in MnGa/Co/Ta, antiferromagnetic coupling plays a dominant role. The switching current density Jc in MnGa/Ta is 8.5 × 107 A/cm2. After inserting 0.8-nm-thick Co2FeAl and Co, theJc becomes 5 × 107 A/cm2 and 9 × 107 A/cm2, respectively. By performing adiabatic harmonic Hall voltage measurements, it is demonstrated that the inserted Co2FeAl layer has mainly enhanced the field-like torques, while in MnGa/Co/Ta the damping-like torques have been enhanced. Finally, the enhanced spin Hall effect (SHE) has also been studied using the spin Hall magnetoresistance measurement. The modulated Jc and SOT are ascribed to the combination of magnetic coupling, Rashba effect and SHE at the interfaces.
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Qiu X, Legrand W, He P, Wu Y, Yu J, Ramaswamy R, Manchon A, Yang H. Enhanced Spin-Orbit Torque via Modulation of Spin Current Absorption. PHYSICAL REVIEW LETTERS 2016; 117:217206. [PMID: 27911535 DOI: 10.1103/physrevlett.117.217206] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Indexed: 06/06/2023]
Abstract
The magnitude of spin-orbit torque (SOT), exerted to a ferromagnet (FM) from an adjacent heavy metal (HM), strongly depends on the amount of spin current absorbed in the FM. We exploit the large spin absorption at the Ru interface to manipulate the SOTs in HM/FM/Ru multilayers. While the FM thickness is smaller than its spin dephasing length of 1.2 nm, the top Ru layer largely boosts the absorption of spin currents into the FM layer and substantially enhances the strength of SOT acting on the FM. Spin-pumping experiments induced by ferromagnetic resonance support our conclusions that the observed increase in the SOT efficiency can be attributed to an enhancement of the spin-current absorption. A theoretical model that considers both reflected and transmitted mixing conductances at the two interfaces of FM is developed to explain the results.
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Affiliation(s)
- Xuepeng Qiu
- Department of Electrical and Computer Engineering, and NUSNNI, National University of Singapore, Singapore 117576, Singapore
- Shanghai Key Laboratory of Special Artificial Microstructure Materials & School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
| | - William Legrand
- Department of Electrical and Computer Engineering, and NUSNNI, National University of Singapore, Singapore 117576, Singapore
| | - Pan He
- Department of Electrical and Computer Engineering, and NUSNNI, National University of Singapore, Singapore 117576, Singapore
| | - Yang Wu
- Department of Electrical and Computer Engineering, and NUSNNI, National University of Singapore, Singapore 117576, Singapore
| | - Jiawei Yu
- Department of Electrical and Computer Engineering, and NUSNNI, National University of Singapore, Singapore 117576, Singapore
| | - Rajagopalan Ramaswamy
- Department of Electrical and Computer Engineering, and NUSNNI, National University of Singapore, Singapore 117576, Singapore
| | - Aurelien Manchon
- Division of Physical Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia
| | - Hyunsoo Yang
- Department of Electrical and Computer Engineering, and NUSNNI, National University of Singapore, Singapore 117576, Singapore
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Nakayama H, Kanno Y, An H, Tashiro T, Haku S, Nomura A, Ando K. Rashba-Edelstein Magnetoresistance in Metallic Heterostructures. PHYSICAL REVIEW LETTERS 2016; 117:116602. [PMID: 27661708 DOI: 10.1103/physrevlett.117.116602] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Indexed: 06/06/2023]
Abstract
We report the observation of magnetoresistance originating from Rashba spin-orbit coupling (SOC) in a metallic heterostructure: the Rashba-Edelstein (RE) magnetoresistance. We show that the simultaneous action of the direct and inverse RE effects in a Bi/Ag/CoFeB trilayer couples current-induced spin accumulation to the electric resistance. The electric resistance changes with the magnetic-field angle, reminiscent of the spin Hall magnetoresistance, despite the fact that bulk SOC is not responsible for the magnetoresistance. We further found that, even when the magnetization is saturated, the resistance increases with increasing the magnetic-field strength, which is attributed to the Hanle magnetoresistance in this system.
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Affiliation(s)
- Hiroyasu Nakayama
- Department of Applied Physics and Physico-Informatics, Keio University, Yokohama 223-8522, Japan
| | - Yusuke Kanno
- Department of Applied Physics and Physico-Informatics, Keio University, Yokohama 223-8522, Japan
| | - Hongyu An
- Department of Applied Physics and Physico-Informatics, Keio University, Yokohama 223-8522, Japan
| | - Takaharu Tashiro
- Department of Applied Physics and Physico-Informatics, Keio University, Yokohama 223-8522, Japan
| | - Satoshi Haku
- Department of Applied Physics and Physico-Informatics, Keio University, Yokohama 223-8522, Japan
| | - Akiyo Nomura
- Department of Applied Physics and Physico-Informatics, Keio University, Yokohama 223-8522, Japan
| | - Kazuya Ando
- Department of Applied Physics and Physico-Informatics, Keio University, Yokohama 223-8522, Japan
- PRESTO, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan
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Zhang B, Meng KK, Yang MY, Edmonds KW, Zhang H, Cai KM, Sheng Y, Zhang N, Ji Y, Zhao JH, Zheng HZ, Wang KY. Piezo Voltage Controlled Planar Hall Effect Devices. Sci Rep 2016; 6:28458. [PMID: 27329068 PMCID: PMC4916466 DOI: 10.1038/srep28458] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 06/06/2016] [Indexed: 11/09/2022] Open
Abstract
The electrical control of the magnetization switching in ferromagnets is highly desired for future spintronic applications. Here we report on hybrid piezoelectric (PZT)/ferromagnetic (Co2FeAl) devices in which the planar Hall voltage in the ferromagnetic layer is tuned solely by piezo voltages. The change of planar Hall voltage is associated with magnetization switching through 90° in the plane under piezo voltages. Room temperature magnetic NOT and NOR gates are demonstrated based on the piezo voltage controlled Co2FeAl planar Hall effect devices without the external magnetic field. Our demonstration may lead to the realization of both information storage and processing using ferromagnetic materials.
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Affiliation(s)
- Bao Zhang
- SKLSM, Institute of Semiconductors, CAS, P. O. Box 912, Beijing 100083, People's Republic of China
| | - Kang-Kang Meng
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100048, China
| | - Mei-Yin Yang
- SKLSM, Institute of Semiconductors, CAS, P. O. Box 912, Beijing 100083, People's Republic of China
| | - K W Edmonds
- School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Hao Zhang
- SKLSM, Institute of Semiconductors, CAS, P. O. Box 912, Beijing 100083, People's Republic of China
| | - Kai-Ming Cai
- SKLSM, Institute of Semiconductors, CAS, P. O. Box 912, Beijing 100083, People's Republic of China
| | - Yu Sheng
- SKLSM, Institute of Semiconductors, CAS, P. O. Box 912, Beijing 100083, People's Republic of China.,Department of Physics, School of Sciences, University of Science &Technology Beijing, Beijing 100048, China
| | - Nan Zhang
- SKLSM, Institute of Semiconductors, CAS, P. O. Box 912, Beijing 100083, People's Republic of China
| | - Yang Ji
- SKLSM, Institute of Semiconductors, CAS, P. O. Box 912, Beijing 100083, People's Republic of China
| | - Jian-Hua Zhao
- SKLSM, Institute of Semiconductors, CAS, P. O. Box 912, Beijing 100083, People's Republic of China
| | - Hou-Zhi Zheng
- SKLSM, Institute of Semiconductors, CAS, P. O. Box 912, Beijing 100083, People's Republic of China
| | - Kai-You Wang
- SKLSM, Institute of Semiconductors, CAS, P. O. Box 912, Beijing 100083, People's Republic of China
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