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Kumar Mondal A, Majumder S, Kumar Mahato B, Barman S, Otani Y, Barman A. Bias field orientation driven reconfigurable magnonics and magnon-magnon coupling in triangular shaped Ni 80Fe 20nanodot arrays. Nanotechnology 2023; 34:135701. [PMID: 36571848 DOI: 10.1088/1361-6528/acae5e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Accepted: 12/25/2022] [Indexed: 06/17/2023]
Abstract
Reconfigurable magnonics have attracted intense interest due to their myriad advantages including energy efficiency, easy tunability and miniaturization of on-chip data communication and processing devices. Here, we demonstrate efficient reconfigurability of spin-wave (SW) dynamics as well as SW avoided crossing by varying bias magnetic field orientation in triangular shaped Ni80Fe20nanodot arrays. In particular, for a range of in-plane angles of bias field, we achieve mutual coherence between two lower frequency modes leading to a drastic modification in the ferromagnetic resonance frequency. Significant modification in magnetic stray field distribution is observed at the avoided crossing regime due to anisotropic dipolar interaction between two neighbouring dots. Furthermore, using micromagnetic simulations we demonstrate that the hybrid SW modes propagate longer through an array as opposed to the non-interacting modes present in this system, indicating the possibility of coherent energy transfer of hybrid magnon modes. This result paves the way for the development of integrated on-chip magnonic devices operating in the gigahertz frequency regime.
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Affiliation(s)
- Amrit Kumar Mondal
- Department of Condensed Matter and Materials Physics, S. N. Bose National Centre for Basic Sciences, Block JD, Sector-III, Salt Lake, Kolkata 700 106, India
| | - Sudip Majumder
- Department of Condensed Matter and Materials Physics, S. N. Bose National Centre for Basic Sciences, Block JD, Sector-III, Salt Lake, Kolkata 700 106, India
| | - Bipul Kumar Mahato
- Department of Condensed Matter and Materials Physics, S. N. Bose National Centre for Basic Sciences, Block JD, Sector-III, Salt Lake, Kolkata 700 106, India
| | - Saswati Barman
- Institute of Engineering and Management, Sector V, Salt Lake, Kolkata 700091, India
| | - Yoshichika Otani
- CEMS-RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- Institute for Solid State Physics, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581, Japan
| | - Anjan Barman
- Department of Condensed Matter and Materials Physics, S. N. Bose National Centre for Basic Sciences, Block JD, Sector-III, Salt Lake, Kolkata 700 106, India
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2
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Kaneta-Takada S, Kitamura M, Arai S, Arai T, Okano R, Anh LD, Endo T, Horiba K, Kumigashira H, Kobayashi M, Seki M, Tabata H, Tanaka M, Ohya S. Giant spin-to-charge conversion at an all-epitaxial single-crystal-oxide Rashba interface with a strongly correlated metal interlayer. Nat Commun 2022; 13:5631. [PMID: 36163469 PMCID: PMC9512910 DOI: 10.1038/s41467-022-33350-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 09/12/2022] [Indexed: 11/30/2022] Open
Abstract
The two-dimensional electron gas (2DEG) formed at interfaces between SrTiO3 (STO) and other oxide insulating layers is promising for use in efficient spin-charge conversion due to the large Rashba spin-orbit interaction (RSOI). However, these insulating layers on STO prevent the propagation of a spin current injected from an adjacent ferromagnetic layer. Moreover, the mechanism of the spin-current flow in these insulating layers is still unexplored. Here, using a strongly correlated polar-metal LaTiO3+δ (LTO) interlayer and the 2DEG formed at the LTO/STO interface in an all-epitaxial heterostructure, we demonstrate giant spin-to-charge current conversion efficiencies, up to ~190 nm, using spin-pumping ferromagnetic-resonance voltage measurements. This value is the highest among those reported for all materials, including spin Hall systems. Our results suggest that the strong on-site Coulomb repulsion in LTO and the giant RSOI of LTO/STO may be the key to efficient spin-charge conversion with suppressed spin-flip scattering. Our findings highlight the hidden inherent possibilities of oxide interfaces for spin-orbitronics applications. The interface between perovskite-oxide SrTiO3 and other oxides realizes efficient spin-to-charge current conversion; however, the typically insulating oxides hinder the propagation of spin-currents. Here the authors achieve a record efficiency by replacing an oxide insulator with a strongly-correlated polar metal.
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Affiliation(s)
- Shingo Kaneta-Takada
- Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
| | - Miho Kitamura
- Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki, 305-0801, Japan
| | - Shoma Arai
- Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Takuma Arai
- Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Ryo Okano
- Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Le Duc Anh
- Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.,PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan
| | - Tatsuro Endo
- Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Koji Horiba
- Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki, 305-0801, Japan
| | - Hiroshi Kumigashira
- Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki, 305-0801, Japan.,Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University, Sendai, Miyagi, 980-8577, Japan
| | - Masaki Kobayashi
- Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.,Center for Spintronics Research Network (CSRN), The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Munetoshi Seki
- Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.,Center for Spintronics Research Network (CSRN), The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Hitoshi Tabata
- Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.,Center for Spintronics Research Network (CSRN), The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Masaaki Tanaka
- Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan. .,Center for Spintronics Research Network (CSRN), The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
| | - Shinobu Ohya
- Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan. .,Center for Spintronics Research Network (CSRN), The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
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Lee WY, Park NW, Kang MS, Kim GS, Yoon YG, Lee S, Choi KY, Kim KS, Kim JH, Seong MJ, Kikkawa T, Saitoh E, Lee SK. Extrinsic Surface Magnetic Anisotropy Contribution in Pt/Y 3Fe 5O 12 Interface in Longitudinal Spin Seebeck Effect by Graphene Interlayer. ACS Appl Mater Interfaces 2021; 13:45097-45104. [PMID: 34496563 DOI: 10.1021/acsami.1c13180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
A recent study found that magnetization curves for Y3Fe5O12 (YIG) slab and thick films (>20 μm thick) differed from bulk system curves by their longitudinal spin Seebeck effect in a Pt/YIG bilayer system. The deviation was due to intrinsic YIG surface magnetic anisotropy, which is difficult to adopt extrinsic surface magnetic anisotropy even when in contact with other materials on the YIG surface. This study experimentally demonstrates evidence for extrinsic YIG surface magnetic anisotropy when in contact with a diamagnetic graphene interlayer by observing the spin Seebeck effect, directly proving intrinsic YIG surface magnetic anisotropy interruption. We show the Pt/YIG bilayer system graphene interlayer role using large area single and multilayered graphenes using the longitudinal spin Seebeck effect at room temperature, and address the presence of surface magnetic anisotropy due to magnetic proximity between graphene and YIG layer. These findings suggest a promising route to understand new physics of spin Seebeck effect in spin transport.
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Affiliation(s)
- Won-Yong Lee
- Department of Physics, Chung-Ang University, Seoul 06974, Republic of Korea
| | - No-Won Park
- Department of Physics, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Min-Sung Kang
- Department of Physics, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Gil-Sung Kim
- Department of Physics, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Young-Gui Yoon
- Department of Physics, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Suheon Lee
- Deopartment of Physics, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Kwang-Yong Choi
- Deopartment of Physics, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Keun Soo Kim
- Department of Physics and Astronomy, Sejong University, Seoul 05006, Republic of Korea
| | - Jin-Hyuk Kim
- Department of Physics, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Maeng-Je Seong
- Department of Physics, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Takashi Kikkawa
- Department of Applied Physics, The University of Tokyo, Tokyo 113-8656, Japan
| | - Eiji Saitoh
- Department of Applied Physics, The University of Tokyo, Tokyo 113-8656, Japan
- WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
- Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
| | - Sang-Kwon Lee
- Department of Physics, Chung-Ang University, Seoul 06974, Republic of Korea
- WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
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Wang H, Madami M, Chen J, Sheng L, Zhao M, Zhang Y, He W, Guo C, Jia H, Liu S, Song Q, Han X, Yu D, Gubbiotti G, Yu H. Tunable Damping in Magnetic Nanowires Induced by Chiral Pumping of Spin Waves. ACS Nano 2021; 15:9076-9083. [PMID: 33977721 DOI: 10.1021/acsnano.1c02250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Spin-current and spin-wave-based devices have been considered as promising candidates for next-generation information transport and processing and wave-based computing technologies with low-power consumption. Spin pumping has attracted tremendous attention and has led to interesting phenomena, including the line width broadening, which indicates damping enhancement due to energy dissipation. Recently, chiral spin pumping of spin waves has been experimentally realized and theoretically studied in magnetic nanostructures. Here, we experimentally observe by Brillouin light scattering (BLS) microscopy the line width broadening sensitive to magnetization configuration in a hybrid metal-insulator nanostructure consisting of a Co nanowire grating dipolarly coupled to a planar continuous YIG film, consistent with the results of the measured hysteresis loop. Tunable line width broadening has been confirmed independently by propagating spin-wave spectroscopy, where unidirectional spin waves are detected. Position-dependent BLS measurement unravels an oscillating-like behavior of magnon populations in Co nanowire grating, which might result from the magnon trap effect. These results are thus attractive for reconfigurable nanomagnonics devices.
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Affiliation(s)
- Hanchen Wang
- Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China
| | - Marco Madami
- Dipartimento di Fisica e Geologia, Università di Perugia, Perugia I-06123, Italy
| | - Jilei Chen
- Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China
- Shenzhen Institute for Quantum Science and Engineering (SIQSE), and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Lutong Sheng
- Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China
| | - Mingkun Zhao
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
| | - Yu Zhang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
| | - Wenqing He
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
| | - Chenyang Guo
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
| | - Hao Jia
- Shenzhen Institute for Quantum Science and Engineering (SIQSE), and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Song Liu
- Shenzhen Institute for Quantum Science and Engineering (SIQSE), and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Qiuming Song
- Shenzhen Institute for Quantum Science and Engineering (SIQSE), and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Xiufeng Han
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
| | - Dapeng Yu
- Shenzhen Institute for Quantum Science and Engineering (SIQSE), and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Gianluca Gubbiotti
- Dipartimento di Fisica e Geologia, Istituto Officina dei Materiali del Consiglio Nazionale delle Ricerche (IOM-CNR), Sede di Perugia, Via A. Pascoli, Perugia I-06123, Italy
| | - Haiming Yu
- Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China
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5
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Jin L, Jia K, Zhang D, Liu B, Meng H, Tang X, Zhong Z, Zhang H. Effect of Interfacial Roughness Spin Scattering on the Spin Current Transport in YIG/NiO/Pt Heterostructures. ACS Appl Mater Interfaces 2019; 11:35458-35467. [PMID: 31483597 DOI: 10.1021/acsami.9b12125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Interfacial properties play a vital role in spin current injection from the ferromagnetic (FM) layer into the nonmagnetic (NM) layer. So far, impedance matching and spin-orbit coupling are two important, well-known factors in spin current transport in FM/NM heterostructures. In this work, the spin current transport in Y3Fe5O12 (YIG)/NiO/Pt heterostructures was investigated by spin Hall magnetoresistance and inverse spin Hall effect measurements. By inserting a layer of antiferromagnetic insulator NiO, the magnetic proximity effect affecting the Pt atoms owing to YIG and the anomalous spin Hall voltage can be efficiently blocked. Ferromagnetic resonance and spin pumping measurements verified that the ferromagnetic/antiferromagnetic exchange coupling inhibits transmission of the spin current at the YIG/NiO interface when the NiO layer is thick. Atomic force microscopy and spherical aberration-corrected transmission electron microscopy proved that the strong interfacial roughness-enhanced spin scattering between NiO and Pt can greatly increase both the inverse spin Hall voltage and the spin Hall magnetoresistance when the NiO layer is thin or even discontinuous. This interface roughness-dominated spin scattering mechanism based on the YIG/NiO/Pt heterostructure is a new discovery, and there is significant potential for exploiting this mechanism in the construction of low-dissipation spintronic devices with an efficient spin current injection.
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Affiliation(s)
- Lichuan Jin
- State Key Laboratory of Electronic Thin Films and Integrated Devices , University of Electronic Science and Technology of China , Chengdu , 610054 , China
| | - Kancheng Jia
- State Key Laboratory of Electronic Thin Films and Integrated Devices , University of Electronic Science and Technology of China , Chengdu , 610054 , China
| | - Dainan Zhang
- State Key Laboratory of Electronic Thin Films and Integrated Devices , University of Electronic Science and Technology of China , Chengdu , 610054 , China
| | - Bo Liu
- Zhejiang Hikstor Technology Co., Ltd. , Hangzhou , 310000 , China
| | - Hao Meng
- Zhejiang Hikstor Technology Co., Ltd. , Hangzhou , 310000 , China
| | - Xiaoli Tang
- State Key Laboratory of Electronic Thin Films and Integrated Devices , University of Electronic Science and Technology of China , Chengdu , 610054 , China
| | - Zhiyong Zhong
- State Key Laboratory of Electronic Thin Films and Integrated Devices , University of Electronic Science and Technology of China , Chengdu , 610054 , China
| | - Huaiwu Zhang
- State Key Laboratory of Electronic Thin Films and Integrated Devices , University of Electronic Science and Technology of China , Chengdu , 610054 , China
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Cerqueira C, Qin JY, Dang H, Djeffal A, Le Breton JC, Hehn M, Rojas-Sanchez JC, Devaux X, Suire S, Migot S, Schieffer P, Mussot JG, Łaczkowski P, Anane A, Petit-Watelot S, Stoffel M, Mangin S, Liu Z, Cheng BW, Han XF, Jaffrès H, George JM, Lu Y. Evidence of Pure Spin-Current Generated by Spin Pumping in Interface-Localized States in Hybrid Metal-Silicon-Metal Vertical Structures. Nano Lett 2019; 19:90-99. [PMID: 30472859 DOI: 10.1021/acs.nanolett.8b03386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Due to the difficulty of growing high-quality semiconductors on ferromagnetic metals, the study of spin diffusion transport in Si was limited to lateral geometry devices. In this work, by using an ultrahigh-vacuum wafer-bonding technique, we have successfully fabricated metal-semiconductor-metal CoFeB/MgO/Si/Pt vertical structures. We hereby demonstrate pure spin-current injection and transport in the perpendicular current flow geometry over a distance larger than 2 μm in n-type Si at room temperature. In those experiments, a pure propagating spin current is generated via ferromagnetic resonance spin pumping and converted into a measurable voltage by using the inverse spin Hall effect occurring in the top Pt layer. A systematic study varying both Si and MgO thicknesses reveals the important role played by the localized states at the MgO-Si interface for the spin-current generation. Proximity effects involving indirect exchange interactions between the ferromagnet and the MgO-Si interface states appears to be a prerequisite to establishing the necessary out-of-equilibrium spin population in Si under the spin-pumping action.
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Affiliation(s)
- Carolina Cerqueira
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Sud, Université Paris-Saclay , 91767 , Palaiseau , France
- Laboratoire des Solides Irradiés, École Polytechnique, CNRS, CEA , Université Paris-Saclay , 91128 Palaiseau , France
| | - Jian Yin Qin
- Université de Lorraine , CNRS, Institut Jean Lamour, UMR 7198, campus ARTEM , 2 Allée André Guinier , 54011 Nancy , France
- Beijing National Laboratory of Condensed Matter Physics , Institute of Physics, University of Chinese Academy of Sciences , Beijing 100190 , PR China
| | - Huong Dang
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Sud, Université Paris-Saclay , 91767 , Palaiseau , France
| | - Abdelhak Djeffal
- Université de Lorraine , CNRS, Institut Jean Lamour, UMR 7198, campus ARTEM , 2 Allée André Guinier , 54011 Nancy , France
| | | | - Michel Hehn
- Université de Lorraine , CNRS, Institut Jean Lamour, UMR 7198, campus ARTEM , 2 Allée André Guinier , 54011 Nancy , France
| | - Juan-Carlos Rojas-Sanchez
- Université de Lorraine , CNRS, Institut Jean Lamour, UMR 7198, campus ARTEM , 2 Allée André Guinier , 54011 Nancy , France
| | - Xavier Devaux
- Université de Lorraine , CNRS, Institut Jean Lamour, UMR 7198, campus ARTEM , 2 Allée André Guinier , 54011 Nancy , France
| | - Stéphane Suire
- Université de Lorraine , CNRS, Institut Jean Lamour, UMR 7198, campus ARTEM , 2 Allée André Guinier , 54011 Nancy , France
| | - Sylvie Migot
- Université de Lorraine , CNRS, Institut Jean Lamour, UMR 7198, campus ARTEM , 2 Allée André Guinier , 54011 Nancy , France
| | - Philippe Schieffer
- Univ RennesCNRS, IPR (Institut de Physique de Rennes) - UMR 6251 , F-35000 Rennes , France
| | - Jean-Georges Mussot
- Université de Lorraine , CNRS, Institut Jean Lamour, UMR 7198, campus ARTEM , 2 Allée André Guinier , 54011 Nancy , France
| | - Piotr Łaczkowski
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Sud, Université Paris-Saclay , 91767 , Palaiseau , France
| | - Abdelmadjid Anane
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Sud, Université Paris-Saclay , 91767 , Palaiseau , France
| | - Sebastien Petit-Watelot
- Université de Lorraine , CNRS, Institut Jean Lamour, UMR 7198, campus ARTEM , 2 Allée André Guinier , 54011 Nancy , France
| | - Mathieu Stoffel
- Université de Lorraine , CNRS, Institut Jean Lamour, UMR 7198, campus ARTEM , 2 Allée André Guinier , 54011 Nancy , France
| | - Stéphane Mangin
- Université de Lorraine , CNRS, Institut Jean Lamour, UMR 7198, campus ARTEM , 2 Allée André Guinier , 54011 Nancy , France
| | - Zhi Liu
- State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Center of Materials Science and Optoelectronics Engineering , University of Chinese Academy of Sciences Chinese Academy of Sciences , Beijing 100083 , PR China
| | - Bu Wen Cheng
- State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Center of Materials Science and Optoelectronics Engineering , University of Chinese Academy of Sciences Chinese Academy of Sciences , Beijing 100083 , PR China
| | - Xiu Feng Han
- Beijing National Laboratory of Condensed Matter Physics , Institute of Physics, University of Chinese Academy of Sciences , Beijing 100190 , PR China
| | - Henri Jaffrès
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Sud, Université Paris-Saclay , 91767 , Palaiseau , France
| | - Jean-Marie George
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Sud, Université Paris-Saclay , 91767 , Palaiseau , France
| | - Yuan Lu
- Université de Lorraine , CNRS, Institut Jean Lamour, UMR 7198, campus ARTEM , 2 Allée André Guinier , 54011 Nancy , France
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7
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Noel P, Thomas C, Fu Y, Vila L, Haas B, Jouneau PH, Gambarelli S, Meunier T, Ballet P, Attané JP. Highly Efficient Spin-to-Charge Current Conversion in Strained HgTe Surface States Protected by a HgCdTe Layer. Phys Rev Lett 2018; 120:167201. [PMID: 29756906 DOI: 10.1103/physrevlett.120.167201] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 03/08/2018] [Indexed: 06/08/2023]
Abstract
We report the observation of spin-to-charge current conversion in strained mercury telluride at room temperature, using spin pumping experiments. We show that a HgCdTe barrier can be used to protect the HgTe from direct contact with the ferromagnet, leading to very high conversion rates, with inverse Edelstein lengths up to 2.0±0.5 nm. The influence of the HgTe layer thickness on the conversion efficiency is found to differ strongly from what is expected in spin Hall effect systems. These measurements, associated with the temperature dependence of the resistivity, suggest that these high conversion rates are due to the spin momentum locking property of HgTe surface states.
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Affiliation(s)
- P Noel
- Univ. Grenoble Alpes, CEA, CNRS, Grenoble INP, INAC, SPINTEC, F-38000 Grenoble, France
| | - C Thomas
- Univ. Grenoble Alpes, CEA, LETI, MINATEC Campus, F38054 Grenoble, France
| | - Y Fu
- Univ. Grenoble Alpes, CEA, CNRS, Grenoble INP, INAC, SPINTEC, F-38000 Grenoble, France
| | - L Vila
- Univ. Grenoble Alpes, CEA, CNRS, Grenoble INP, INAC, SPINTEC, F-38000 Grenoble, France
| | - B Haas
- CEA, INAC-MEM, 38054 Grenoble, France
| | | | - S Gambarelli
- CEA, Institut Nanosciences et Cryogénie, SyMMES F-38000 Grenoble, France
| | - T Meunier
- CNRS, Institut NEEL, 38042 Grenoble, France
| | - P Ballet
- Univ. Grenoble Alpes, CEA, LETI, MINATEC Campus, F38054 Grenoble, France
| | - J P Attané
- Univ. Grenoble Alpes, CEA, CNRS, Grenoble INP, INAC, SPINTEC, F-38000 Grenoble, France
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8
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Mitra A, Cespedes O, Ramasse Q, Ali M, Marmion S, Ward M, Brydson RMD, Kinane CJ, Cooper JFK, Langridge S, Hickey BJ. Interfacial Origin of the Magnetisation Suppression of Thin Film Yttrium Iron Garnet. Sci Rep 2017; 7:11774. [PMID: 28924173 PMCID: PMC5603596 DOI: 10.1038/s41598-017-10281-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 07/18/2017] [Indexed: 11/10/2022] Open
Abstract
Yttrium iron garnet has a very high Verdet constant, is transparent in the infrared and is an insulating ferrimagnet leading to its use in optical and magneto-optical applications. Its high Q-factor has been exploited to make resonators and filters in microwave devices, but it also has the lowest magnetic damping of any known material. In this article we describe the structural and magnetic properties of single crystal thin-film YIG where the temperature dependence of the magnetisation reveals a decrease in the low temperature region. In order to understand this complex material we bring a large number of structural and magnetic techniques to bear on the same samples. Through a comprehensive analysis we show that at the substrate -YIG interface, an interdiffusion zone of only 4–6 nm exists. Due to the interdiffusion of Y from the YIG and Gd from the substrate, an addition magnetic layer is formed at the interface whose properties are crucially important in samples with a thickness of YIG less than 200 nm.
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Affiliation(s)
- A Mitra
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - O Cespedes
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - Q Ramasse
- SuperSTEM Laboratory, SciTech Daresbury Campus, Keckwick Lane, Daresbury, WA4 4AD, UK
| | - M Ali
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - S Marmion
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - M Ward
- School of Chemical and Process Engineering, University of Leeds, Leeds, LS2 9JT, UK
| | - R M D Brydson
- School of Chemical and Process Engineering, University of Leeds, Leeds, LS2 9JT, UK
| | - C J Kinane
- Rutherford Appleton Laboratory, ISIS, Science and Technology Facilities Council, Didcot, OX11 0QX, Oxon, UK
| | - J F K Cooper
- Rutherford Appleton Laboratory, ISIS, Science and Technology Facilities Council, Didcot, OX11 0QX, Oxon, UK
| | - S Langridge
- Rutherford Appleton Laboratory, ISIS, Science and Technology Facilities Council, Didcot, OX11 0QX, Oxon, UK
| | - B J Hickey
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK.
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9
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Ok S, Chen W, Sigrist M, Manske D. Effect of quantum tunneling on spin Hall magnetoresistance. J Phys Condens Matter 2017; 29:075802. [PMID: 28032615 DOI: 10.1088/1361-648x/aa50da] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We present a formalism that simultaneously incorporates the effect of quantum tunneling and spin diffusion on the spin Hall magnetoresistance observed in normal metal/ferromagnetic insulator bilayers (such as Pt/Y3Fe5O12) and normal metal/ferromagnetic metal bilayers (such as Pt/Co), in which the angle of magnetization influences the magnetoresistance of the normal metal. In the normal metal side the spin diffusion is known to affect the landscape of the spin accumulation caused by spin Hall effect and subsequently the magnetoresistance, while on the ferromagnet side the quantum tunneling effect is detrimental to the interface spin current which also affects the spin accumulation. The influence of generic material properties such as spin diffusion length, layer thickness, interface coupling, and insulating gap can be quantified in a unified manner, and experiments that reveal the quantum feature of the magnetoresistance are suggested.
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Affiliation(s)
- Seulgi Ok
- Institut für Theoretische Physik, ETH-Zürich, CH-8093 Zürich, Switzerland
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10
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Baker AA, Figueroa AI, Pingstone D, Lazarov VK, van der Laan G, Hesjedal T. Spin pumping in magnetic trilayer structures with an MgO barrier. Sci Rep 2016; 6:35582. [PMID: 27752117 PMCID: PMC5067716 DOI: 10.1038/srep35582] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 10/04/2016] [Indexed: 11/08/2022] Open
Abstract
We present a study of the interaction mechanisms in magnetic trilayer structures with an MgO barrier grown by molecular beam epitaxy. The interlayer exchange coupling, Aex, is determined using SQUID magnetometry and ferromagnetic resonance (FMR), displaying an unexpected oscillatory behaviour as the thickness, tMgO, is increased from 1 to 4 nm. Transmission electron microscopy confirms the continuity and quality of the tunnelling barrier, eliminating the prospect of exchange arising from direct contact between the two ferromagnetic layers. The Gilbert damping is found to be almost independent of the MgO thickness, suggesting the suppression of spin pumping. The element-specific technique of x-ray detected FMR reveals a small dynamic exchange interaction, acting in concert with the static interaction to induce coupled precession across the multilayer stack. These results highlight the potential of spin pumping and spin transfer torque for device applications in magnetic tunnel junctions relying on commonly used MgO barriers.
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Affiliation(s)
- A. A. Baker
- Department of Physics, Clarendon Laboratory, University of Oxford, Oxford, OX1 3PU, United Kingdom
- Magnetic Spectroscopy Group, Diamond Light Source, Didcot, OX11 0DE, United Kingdom
| | - A. I. Figueroa
- Magnetic Spectroscopy Group, Diamond Light Source, Didcot, OX11 0DE, United Kingdom
| | - D. Pingstone
- Department of Physics, University of York, Heslington, York, YO10 5DD, United Kingdom
| | - V. K. Lazarov
- Department of Physics, University of York, Heslington, York, YO10 5DD, United Kingdom
| | - G. van der Laan
- Magnetic Spectroscopy Group, Diamond Light Source, Didcot, OX11 0DE, United Kingdom
| | - T. Hesjedal
- Department of Physics, Clarendon Laboratory, University of Oxford, Oxford, OX1 3PU, United Kingdom
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11
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Wang H, Kally J, Lee JS, Liu T, Chang H, Hickey DR, Mkhoyan KA, Wu M, Richardella A, Samarth N. Surface-State-Dominated Spin-Charge Current Conversion in Topological-Insulator-Ferromagnetic-Insulator Heterostructures. Phys Rev Lett 2016; 117:076601. [PMID: 27563980 DOI: 10.1103/physrevlett.117.076601] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Indexed: 06/06/2023]
Abstract
We report the observation of ferromagnetic resonance-driven spin pumping signals at room temperature in three-dimensional topological insulator thin films-Bi_{2}Se_{3} and (Bi,Sb)_{2}Te_{3}-deposited by molecular beam epitaxy on Y_{3}Fe_{5}O_{12} thin films. By systematically varying the Bi_{2}Se_{3} film thickness, we show that the spin-charge conversion efficiency, characterized by the inverse Rashba-Edelstein effect length (λ_{IREE}), increases dramatically as the film thickness is increased from two quintuple layers, saturating above six quintuple layers. This suggests a dominant role of surface states in spin and charge interconversion in topological-insulator-ferromagnet heterostructures. Our conclusion is further corroborated by studying a series of Y_{3}Fe_{5}O_{12}/(Bi,Sb)_{2}Te_{3} heterostructures. Finally, we use the ferromagnetic resonance linewidth broadening and the inverse Rashba-Edelstein signals to determine the effective interfacial spin mixing conductance and λ_{IREE}.
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Affiliation(s)
- Hailong Wang
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - James Kally
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Joon Sue Lee
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Tao Liu
- Department of Physics, Colorado State University, Fort Collins, Colorado 80523, USA
| | - Houchen Chang
- Department of Physics, Colorado State University, Fort Collins, Colorado 80523, USA
| | - Danielle Reifsnyder Hickey
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - K Andre Mkhoyan
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Mingzhong Wu
- Department of Physics, Colorado State University, Fort Collins, Colorado 80523, USA
| | - Anthony Richardella
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Nitin Samarth
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
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12
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Lin W, Chen K, Zhang S, Chien CL. Enhancement of Thermally Injected Spin Current through an Antiferromagnetic Insulator. Phys Rev Lett 2016; 116:186601. [PMID: 27203336 DOI: 10.1103/physrevlett.116.186601] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Indexed: 06/05/2023]
Abstract
We report a large enhancement of thermally injected spin current in normal metal (NM)/antiferromagnet (AF)/yttrium iron garnet (YIG), where a thin AF insulating layer of NiO or CoO can enhance the spin current from YIG to a NM by up to a factor of 10. The spin current enhancement in NM/AF/YIG, with a pronounced maximum near the Néel temperature of the thin AF layer, has been found to scale linearly with the spin-mixing conductance at the NM/YIG interface for NM=3d, 4d, and 5d metals. Calculations of spin current enhancement and spin mixing conductance are qualitatively consistent with the experimental results.
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Affiliation(s)
- Weiwei Lin
- Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Kai Chen
- Department of Physics, University of Arizona, Tucson, Arizona 85721, USA
| | - Shufeng Zhang
- Department of Physics, University of Arizona, Tucson, Arizona 85721, USA
| | - C L Chien
- Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA
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13
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Baker AA, Figueroa AI, Love CJ, Cavill SA, Hesjedal T, van der Laan G. Anisotropic Absorption of Pure Spin Currents. Phys Rev Lett 2016; 116:047201. [PMID: 26871353 DOI: 10.1103/physrevlett.116.047201] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Indexed: 06/05/2023]
Abstract
Spin transfer in magnetic multilayers offers the possibility of ultrafast, low-power device operation. We report a study of spin pumping in spin valves, demonstrating that a strong anisotropy of spin pumping from the source layer can be induced by an angular dependence of the total Gilbert damping parameter, α, in the spin sink layer. Using lab- and synchrotron-based ferromagnetic resonance, we show that an in-plane variation of damping in a crystalline Co_{50}Fe_{50} layer leads to an anisotropic α in a polycrystalline Ni_{81}Fe_{19} layer. This anisotropy is suppressed above the spin diffusion length in Cr, which is found to be 8 nm, and is independent of static exchange coupling in the spin valve. These results offer a valuable insight into the transmission and absorption of spin currents, and a mechanism by which enhanced spin torques and angular control may be realized for next-generation spintronic devices.
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Affiliation(s)
- A A Baker
- Magnetic Spectroscopy Group, Diamond Light Source, Didcot OX11 0DE, United Kingdom
- Department of Physics, Clarendon Laboratory, University of Oxford, Oxford OX1 3PU, United Kingdom
| | - A I Figueroa
- Magnetic Spectroscopy Group, Diamond Light Source, Didcot OX11 0DE, United Kingdom
| | - C J Love
- Magnetic Spectroscopy Group, Diamond Light Source, Didcot OX11 0DE, United Kingdom
- Department of Physics, University of York, York YO10 5DD, United Kingdom
| | - S A Cavill
- Department of Physics, University of York, York YO10 5DD, United Kingdom
- Diamond Light Source, Didcot OX11 0DE, United Kingdom
| | - T Hesjedal
- Department of Physics, Clarendon Laboratory, University of Oxford, Oxford OX1 3PU, United Kingdom
- Diamond Light Source, Didcot OX11 0DE, United Kingdom
| | - G van der Laan
- Magnetic Spectroscopy Group, Diamond Light Source, Didcot OX11 0DE, United Kingdom
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14
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Tashiro T, Matsuura S, Nomura A, Watanabe S, Kang K, Sirringhaus H, Ando K. Spin-current emission governed by nonlinear spin dynamics. Sci Rep 2015; 5:15158. [PMID: 26472712 DOI: 10.1038/srep15158] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 09/16/2015] [Indexed: 11/29/2022] Open
Abstract
Coupling between conduction electrons and localized magnetization is responsible for a variety of phenomena in spintronic devices. This coupling enables to generate spin currents from dynamical magnetization. Due to the nonlinearity of magnetization dynamics, the spin-current emission through the dynamical spin-exchange coupling offers a route for nonlinear generation of spin currents. Here, we demonstrate spin-current emission governed by nonlinear magnetization dynamics in a metal/magnetic insulator bilayer. The spin-current emission from the magnetic insulator is probed by the inverse spin Hall effect, which demonstrates nontrivial temperature and excitation power dependences of the voltage generation. The experimental results reveal that nonlinear magnetization dynamics and enhanced spin-current emission due to magnon scatterings are triggered by decreasing temperature. This result illustrates the crucial role of the nonlinear magnon interactions in the spin-current emission driven by dynamical magnetization, or nonequilibrium magnons, from magnetic insulators.
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15
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Baker AA, Figueroa AI, Collins-McIntyre LJ, van der Laan G, Hesjedal T. Spin pumping in ferromagnet-topological insulator-ferromagnet heterostructures. Sci Rep 2015; 5:7907. [PMID: 25601364 PMCID: PMC4298741 DOI: 10.1038/srep07907] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 12/19/2014] [Indexed: 11/20/2022] Open
Abstract
Topological insulators (TIs) are enticing prospects for the future of spintronics due to their large spin-orbit coupling and dissipationless, counter-propagating conduction channels in the surface state. However, a means to interact with and exploit the topological surface state remains elusive. Here, we report a study of spin pumping at the TI-ferromagnet interface, investigating spin transfer dynamics in a spin-valve like structure using element specific time-resolved x-ray magnetic circular dichroism, and ferromagnetic resonance. Gilbert damping increases approximately linearly with increasing TI thickness, indicating efficient behaviour as a spin sink. However, layer-resolved measurements suggest that a dynamic coupling is limited. These results shed new light on the spin dynamics of this novel material class, and suggest great potential for TIs in spintronic devices, through their novel magnetodynamics that persist even up to room temperature.
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Affiliation(s)
- A. A. Baker
- Department of Physics, Clarendon Laboratory, University of Oxford, Oxford, OX1 3PU, United Kingdom
- Magnetic Spectroscopy Group, Diamond Light Source, Didcot, OX11 0DE, United Kingdom
| | - A. I. Figueroa
- Magnetic Spectroscopy Group, Diamond Light Source, Didcot, OX11 0DE, United Kingdom
| | - L. J. Collins-McIntyre
- Department of Physics, Clarendon Laboratory, University of Oxford, Oxford, OX1 3PU, United Kingdom
| | - G. van der Laan
- Magnetic Spectroscopy Group, Diamond Light Source, Didcot, OX11 0DE, United Kingdom
| | - T. Hesjedal
- Department of Physics, Clarendon Laboratory, University of Oxford, Oxford, OX1 3PU, United Kingdom
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16
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Abstract
We observe highly efficient dynamic spin injection from Y3Fe5O12 (YIG) into NiO, an antiferromagnetic (AF) insulator, via strong coupling, and robust spin propagation in NiO up to 100-nm thickness mediated by its AF spin correlations. Strikingly, the insertion of a thin NiO layer between YIG and Pt significantly enhances the spin currents driven into Pt, suggesting exceptionally high spin transfer efficiency at both YIG/NiO and NiO/Pt interfaces. This offers a powerful platform for studying AF spin pumping and AF dynamics as well as for exploration of spin manipulation in tailored structures comprising metallic and insulating ferromagnets, antiferromagnets, and nonmagnetic materials.
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Affiliation(s)
- Hailong Wang
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA
| | - Chunhui Du
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA
| | - P Chris Hammel
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA
| | - Fengyuan Yang
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA
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17
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Wang HL, Du CH, Pu Y, Adur R, Hammel PC, Yang FY. Scaling of spin Hall angle in 3d, 4d, and 5d metals from Y3Fe5O12/metal spin pumping. Phys Rev Lett 2014; 112:197201. [PMID: 24877962 DOI: 10.1103/physrevlett.112.197201] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Indexed: 06/03/2023]
Abstract
We have investigated spin pumping from Y3Fe5O12 thin films into Cu, Ag, Ta, W, Pt, and Au with varying spin-orbit coupling strengths. From measurements of Gilbert damping enhancement and inverse spin Hall signals spanning 3 orders of magnitude, we determine the spin Hall angles and interfacial spin mixing conductances for the six metals. The spin Hall angles largely vary as Z(4) (Z: atomic number), corroborating the role of spin-orbit coupling. Amongst the four 5d metals, the variation of the spin Hall angle is dominated by the sensitivity of the d-orbital moment to the d-electron count, confirming theoretical predictions.
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Affiliation(s)
- H L Wang
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA
| | - C H Du
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA
| | - Y Pu
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA
| | - R Adur
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA
| | - P C Hammel
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA
| | - F Y Yang
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA
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