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Cai M, Hao Q, Liu J, Dai H, Wang X, Chen X, Wang H, Xing Y, Chen H, Zhang A, Zhai T, Han J. Topological Magneto-optical Effect from Skyrmions in Two-Dimensional Ferromagnets. ACS NANO 2024. [PMID: 39058355 DOI: 10.1021/acsnano.3c11480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/28/2024]
Abstract
Skyrmions in two-dimensional (2D) magnetic materials are considered as ideal candidates for information carriers in next-generation spintronic devices. However, conventional methods for elucidating the physical properties of skyrmions have limited the development of skyrmions in diverse 2D magnetic material systems due to their requirements for electrical conductivity. To overcome this limitation, we propose to utilize an optical method (magneto-optical Kerr technique) to detect the skyrmions in 2D magnetic materials. Herein, the graphene/Fe3GeTe2/graphene vertical van der Waals (vdW) heterostructure devices are fabricated to generate stabilized skyrmions by applying out-of-plane current. In combination with magnetic circular dichroism measurements, we observe topological-reflective magnetic circular dichroism (T-RMCD) effects in Fe3GeTe2 flakes and attribute the peak-shaped component in T-RMCD to the annihilation of skyrmion magnetic domains. Notably, the T-RMCD signal can maintain up to a temperature as high as the Curie temperature of Fe3GeTe2 flakes (∼200 K). Our work provides a universal, contactless, and nondestructive approach for studying the physical properties of skyrmions in 2D vdW magnetic materials while adding another degree of freedom to the modulation of skyrmions.
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Affiliation(s)
- Menghao Cai
- Wuhan National High Magnetic Field Center and Department of Physics, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Qinghua Hao
- Wuhan National High Magnetic Field Center and Department of Physics, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Jie Liu
- State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Hongwei Dai
- Wuhan National High Magnetic Field Center and Department of Physics, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Xia Wang
- School of Elementary Education, Wuhan City Polytechnic, Wuhan 430074, P. R. China
| | - Xiaodie Chen
- Wuhan National High Magnetic Field Center and Department of Physics, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Haoyun Wang
- State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Yuntong Xing
- Wuhan National High Magnetic Field Center and Department of Physics, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Hongjing Chen
- Wuhan National High Magnetic Field Center and Department of Physics, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Aoyu Zhang
- Wuhan National High Magnetic Field Center and Department of Physics, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Tianyou Zhai
- State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Junbo Han
- Wuhan National High Magnetic Field Center and Department of Physics, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
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2
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Zhou Y, Li S, Liang X, Zhou Y. Topological Spin Textures: Basic Physics and Devices. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2312935. [PMID: 38861696 DOI: 10.1002/adma.202312935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 05/24/2024] [Indexed: 06/13/2024]
Abstract
In the face of escalating modern data storage demands and the constraints of Moore's Law, exploring spintronic solutions, particularly the devices based on magnetic skyrmions, has emerged as a promising frontier in scientific research. Since the first experimental observation of skyrmions, topological spin textures have been extensively studied for their great potential as efficient information carriers in spintronic devices. However, significant challenges have emerged alongside this progress. This review aims to synthesize recent advances in skyrmion research while addressing the major issues encountered in the field. Additionally, current research on promising topological spin structures in addition to skyrmions is summarized. Beyond 2D structures, exploration also extends to 1D magnetic solitons and 3D spin textures. In addition, a diverse array of emerging magnetic materials is introduced, including antiferromagnets and 2D van der Waals magnets, broadening the scope of potential materials hosting topological spin textures. Through a systematic examination of magnetic principles, topological categorization, and the dynamics of spin textures, a comprehensive overview of experimental and theoretical advances in the research of topological magnetism is provided. Finally, both conventional and unconventional applications are summarized based on spin textures proposed thus far. This review provides an outlook on future development in applied spintronics.
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Affiliation(s)
- Yuqing Zhou
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong, 518172, China
| | - Shuang Li
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong, 518172, China
| | - Xue Liang
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong, 518172, China
| | - Yan Zhou
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong, 518172, China
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3
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Roy P, Zhang D, Mazza AR, Cucciniello N, Kunwar S, Zeng H, Chen A, Jia Q. Manipulating topological Hall-like signatures by interface engineering in epitaxial ruthenate/manganite heterostructures. NANOSCALE 2023; 15:17589-17598. [PMID: 37873761 DOI: 10.1039/d3nr02407e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
Topologically protected non-trivial spin textures (e.g. skyrmions) give rise to a novel phenomenon called the topological Hall effect (THE) and have promising implications in future energy-efficient nanoelectronic and spintronic devices. Here, we have studied the Hall effect in SrRuO3/La0.42Ca0.58MnO3 (SRO/LCMO) bilayers. Our investigation suggests that pure SRO has hard and soft magnetic characteristics but the anomalous Hall effect (AHE) in SRO is governed by the high coercivity phase. We have shown that the proximity effect of a soft magnetic LCMO on SRO plays a critical role in interfacial magnetic coupling and transport properties in SRO. Upon reducing the SRO thickness in the bilayer, the proximity effect becomes the dominant feature, enhancing the magnitude and temperature range of THE-like signatures. The THE-like features in bilayers can be explained by a diffusive Berry phase transition model in the presence of an emergent magnetic state due to interface coupling. This work provides an alternative understanding of THE-like signatures and their manipulation in SRO-based heterostructures, bilayers and superlattices.
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Affiliation(s)
- Pinku Roy
- Department of Materials Design and Innovation, University at Buffalo - The State University of New York, Buffalo, NY 14260, USA.
- Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
| | - Di Zhang
- Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
| | - Alessandro R Mazza
- Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
| | - Nicholas Cucciniello
- Department of Materials Design and Innovation, University at Buffalo - The State University of New York, Buffalo, NY 14260, USA.
- Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
| | - Sundar Kunwar
- Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
| | - Hao Zeng
- Department of Physics, University at Buffalo - The State University of New York, Buffalo, NY 14260, USA
| | - Aiping Chen
- Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
| | - Quanxi Jia
- Department of Materials Design and Innovation, University at Buffalo - The State University of New York, Buffalo, NY 14260, USA.
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4
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Wang G, Hu T, Xiong Y, Liu X, Shen S, Wang J, Che M, Cui Z, Zhang Y, Yang L, Li Z, Lu Y, Tian M. Electric-field control of reversible electronic and magnetic transitions in two-dimensional oxide monolayer magnets. Sci Bull (Beijing) 2023; 68:1632-1639. [PMID: 37429776 DOI: 10.1016/j.scib.2023.06.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 05/27/2023] [Accepted: 06/25/2023] [Indexed: 07/12/2023]
Abstract
Atomically thin oxide magnetic materials are highly desirable due to the promising potential to integrate two-dimensional (2D) magnets into next-generation spintronics. Therefore, 2D oxide magnetism is expected to be effectively tuned by the magnetic and electrical fields, holding prospective for future low-dissipation electronic devices. However, the electric-field control of 2D oxide monolayer magnetism has rarely been reported. Here, we present the realization of 2D monolayer magnetism in oxide (SrRuO3)1/(SrTiO3)N (N = 1, 3) superlattices that shows an efficient and reversible phase transition through electric-field controlled proton (H+) evolution. By using ionic liquid gating to modulate the proton concentration in (SrRuO3)1/(SrTiO3)1 superlattice, an electric-field induced metal-insulator transition was observed, along with gradually suppressed magnetic ordering and modulated magnetic anisotropy. Theoretical analysis reveals that proton intercalation plays a crucial role in both electronic and magnetic phase transitions. Strikingly, SrTiO3 layers can act as a proton sieve, which have a significant influence on proton evolution. Our work stimulates the tuning functionality of 2D oxide monolayer magnetism by voltage control, providing potential for future energy-efficient electronics.
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Affiliation(s)
- Guopeng Wang
- School of Physics and Optoelectronics Engineering, Anhui University, Hefei 230601, China.
| | - Tao Hu
- School of Physics and Optoelectronics Engineering, Anhui University, Hefei 230601, China
| | - Yimin Xiong
- School of Physics and Optoelectronics Engineering, Anhui University, Hefei 230601, China; Hefei National Laboratory, Hefei 230028, China
| | - Xue Liu
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China
| | - Shengchun Shen
- Department of Physics, University of Science and Technology of China, Hefei 230026, China
| | - Jianlin Wang
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China; Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei 230026, China
| | - Mengqian Che
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Zhangzhang Cui
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China; Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei 230026, China.
| | - Yingying Zhang
- State Key Laboratory for New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
| | - Luyi Yang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Zhengcao Li
- State Key Laboratory for New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
| | - Yalin Lu
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China; Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei 230026, China
| | - Mingliang Tian
- School of Physics and Optoelectronics Engineering, Anhui University, Hefei 230601, China.
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5
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Hao L, Yi D, Wang M, Liu J, Yu P. Emergent quantum phenomena in atomically engineered iridate heterostructures. FUNDAMENTAL RESEARCH 2023; 3:313-321. [PMID: 38933764 PMCID: PMC11197666 DOI: 10.1016/j.fmre.2022.09.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Revised: 09/22/2022] [Accepted: 09/25/2022] [Indexed: 11/06/2022] Open
Abstract
Over the last few years, researches in iridates have developed into an exciting field with the discovery of numerous emergent phenomena, interesting physics, and intriguing functionalities. Among the studies, iridate-based artificial structures play a crucial role owing to their extreme flexibility and tunability in lattice symmetry, chemical composition, and crystal dimensionality. In this article, we present an overview of the recent progress regarding iridate-based artificial structures. We first explicitly introduce several essential concepts in iridates. Then, we illustrate important findings on representative SrIrO3/SrTiO3 superlattices, heterostructures comprised of SrIrO3 and magnetic oxides, and their response to external electric-field stimuli. Finally, we comment on existing problems and promising future directions in this exciting field.
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Affiliation(s)
- Lin Hao
- Anhui Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Di Yi
- State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
| | - Meng Wang
- RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198, Japan
| | - Jian Liu
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Pu Yu
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Beijing 100084, China
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6
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Schöpf J, Thampi A, Milde P, Ivaneyko D, Kondovych S, Kononenko DY, Eng LM, Jin L, Yang L, Wysocki L, van Loosdrecht PHM, Richter K, Yershov KV, Wolf D, Lubk A, Lindfors-Vrejoiu I. Néel Skyrmion Bubbles in La 0.7Sr 0.3Mn 1-xRu xO 3 Multilayers. NANO LETTERS 2023; 23:3532-3539. [PMID: 37018631 DOI: 10.1021/acs.nanolett.3c00693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Ferromagnetic La0.7Sr0.3Mn1-xRuxO3 epitaxial multilayers with controlled variation of the Ru/Mn content were synthesized to engineer canted magnetic anisotropy and variable exchange interactions, and to explore the possibility of generating a Dzyaloshinskii-Moriya interaction. The ultimate aim of the multilayer design is to provide the conditions for the formation of domains with nontrivial magnetic topology in an oxide thin film system. Employing magnetic force microscopy and Lorentz transmission electron microscopy in varying perpendicular magnetic fields, magnetic stripe domains separated by Néel-type domain walls as well as Néel skyrmions smaller than 100 nm in diameter were observed. These findings are consistent with micromagnetic modeling, taking into account a sizable Dzyaloshinskii-Moriya interaction arising from the inversion symmetry breaking and possibly from strain effects in the multilayer system.
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Affiliation(s)
- Jörg Schöpf
- II. Physics Institute, University of Cologne, 50937 Cologne, Germany
| | - Arsha Thampi
- Institute for Solid State Research, IFW Dresden, 01069 Dresden, Germany
| | - Peter Milde
- Institute of Applied Physics, TU Dresden, 01062 Dresden, Germany
| | - Dmytro Ivaneyko
- Institute of Applied Physics, TU Dresden, 01062 Dresden, Germany
| | - Svitlana Kondovych
- Institute for Theoretical Solid State Physics, IFW Dresden, 01069 Dresden, Germany
| | - Denys Y Kononenko
- Institute for Theoretical Solid State Physics, IFW Dresden, 01069 Dresden, Germany
| | - Lukas M Eng
- Institute of Applied Physics, TU Dresden, 01062 Dresden, Germany
- ct.qmat, Dresden-Würzburg Cluster of Excellence-EXC 2147, TU Dresden, 01062 Dresden, Germany
| | - Lei Jin
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Lin Yang
- II. Physics Institute, University of Cologne, 50937 Cologne, Germany
| | - Lena Wysocki
- II. Physics Institute, University of Cologne, 50937 Cologne, Germany
| | | | - Kornel Richter
- Faculty of Sciences, Pavol Jozef Safarik University, Park Angelinum 9, 041 54 Kosice, Slovakia
| | - Kostiantyn V Yershov
- Institute for Theoretical Solid State Physics, IFW Dresden, 01069 Dresden, Germany
- Bogolyubov Institute for Theoretical Physics of the National Academy of Sciences of Ukraine, 03143 Kyiv, Ukraine
| | - Daniel Wolf
- Institute for Solid State Research, IFW Dresden, 01069 Dresden, Germany
| | - Axel Lubk
- Institute for Solid State Research, IFW Dresden, 01069 Dresden, Germany
- Institute of Solid State and Materials Physics, TU Dresden, 01062 Dresden, Germany
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7
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Liu R, Si L, Niu W, Zhang X, Chen Z, Zhu C, Zhuang W, Chen Y, Zhou L, Zhang C, Wang P, Song F, Tang L, Xu Y, Zhong Z, Zhang R, Wang X. Light-Induced Mott-Insulator-to-Metal Phase Transition in Ultrathin Intermediate-Spin Ferromagnetic Perovskite Ruthenates. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2211612. [PMID: 36626850 DOI: 10.1002/adma.202211612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 01/06/2023] [Indexed: 06/17/2023]
Abstract
Light control of emergent quantum phenomena is a widely used external stimulus for quantum materials. Generally, perovskite strontium ruthenate SrRuO3 has an itinerant ferromagnetism with a low-spin state. However, the phase of intermediate-spin (IS) ferromagnetic metallic state has never been seen. Here, by means of UV-light irradiation, a photocarrier-doping-induced Mott-insulator-to-metal phase transition is shown in a few atomic layers of perovskite IS ferromagnetic SrRuO3- δ . This new metastable IS metallic phase can be reversibly regulated due to the convenient photocharge transfer from SrTiO3 substrates to SrRuO3- δ ultrathin films. These dynamical mean-field theory calculations further verify such photoinduced electronic phase transformation, owing to oxygen vacancies and orbital reconstruction. The optical manipulation of charge-transfer finesse is an alternative pathway toward discovering novel metastable phases in strongly correlated systems and facilitates potential light-controlled device applications in optoelectronics and spintronics.
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Affiliation(s)
- Ruxin Liu
- Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Liang Si
- School of Physics, Northwest University, Xi'an, 710127, China
- Institute of Solid State Physics, Vienna University of Technology, Vienna, 1040, Austria
| | - Wei Niu
- Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
- School of Science, Nanjing University of Posts and Telecommunications, Nanjing, 210023, China
| | - Xu Zhang
- Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Zhongqiang Chen
- Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Changzheng Zhu
- Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Wenzhuo Zhuang
- Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Yongda Chen
- Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Liqi Zhou
- College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, China
| | - Chunchen Zhang
- College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, China
| | - Peng Wang
- College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, China
- Department of Physics, University of Warwick, Coventry, CV4 7AL, UK
| | - Fengqi Song
- School of Physics, Nanjing University, Nanjing, 210093, China
| | - Lin Tang
- Department of Physics, Tsinghua University, Beijing, 100084, China
| | - Yongbing Xu
- Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Zhicheng Zhong
- Key Laboratory of Magnetic Materials and Devices, Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering (NIMTE), Chinese Academy of Sciences, Ningbo, 315201, China
| | - Rong Zhang
- Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
- Department of Physics, Xiamen University, Xiamen, 316005, China
| | - Xuefeng Wang
- Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
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8
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Han H, Zhou H, Guillemard C, Valvidares M, Sharma A, Li Y, Sharma AK, Kostanovskiy I, Ernst A, Parkin SSP. Reversal of Anomalous Hall Effect and Octahedral Tilting in SrRuO 3 Thin Films via Hydrogen Spillover. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2207246. [PMID: 36271718 DOI: 10.1002/adma.202207246] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 09/18/2022] [Indexed: 06/16/2023]
Abstract
The perovskite SrRuO3 (SRO) is a strongly correlated oxide whose physical and structural properties are strongly intertwined. Notably, SRO is an itinerant ferromagnet that exhibits a large anomalous Hall effect (AHE) whose sign can be readily modified. Here, a hydrogen spillover method is used to tailor the properties of SRO thin films via hydrogen incorporation. It is found that the magnetization and Curie temperature of the films are strongly reduced and, at the same time, the structure evolves from an orthorhombic to a tetragonal phase as the hydrogen content is increased up to ≈0.9 H per SRO formula unit. The structural phase transition is shown, via in situ crystal truncation rod measurements, to be related to tilting of the RuO6 octahedral units. The significant changes observed in magnetization are shown, via density functional theory (DFT), to be a consequence of shifts in the Fermi level. The reported findings provide new insights into the physical properties of SRO via tailoring its lattice symmetry and emergent physical phenomena via the hydrogen spillover technique.
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Affiliation(s)
- Hyeon Han
- Nano Systems from Ions, Spins, and Electrons (NISE), Max Planck Institute of Microstructure Physics, 06120, Halle (Saale), Germany
| | - Hua Zhou
- Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Charles Guillemard
- ALBA Synchrotron Light Source, Cerdanyola del Vallès, Barcelona, E-08290, Spain
| | - Manuel Valvidares
- ALBA Synchrotron Light Source, Cerdanyola del Vallès, Barcelona, E-08290, Spain
| | - Arpit Sharma
- Nano Systems from Ions, Spins, and Electrons (NISE), Max Planck Institute of Microstructure Physics, 06120, Halle (Saale), Germany
| | - Yan Li
- Materials Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Ankit K Sharma
- Nano Systems from Ions, Spins, and Electrons (NISE), Max Planck Institute of Microstructure Physics, 06120, Halle (Saale), Germany
| | - Ilya Kostanovskiy
- Nano Systems from Ions, Spins, and Electrons (NISE), Max Planck Institute of Microstructure Physics, 06120, Halle (Saale), Germany
| | - Arthur Ernst
- Nano Systems from Ions, Spins, and Electrons (NISE), Max Planck Institute of Microstructure Physics, 06120, Halle (Saale), Germany
- Institute for Theoretical Physics, Johannes Kepler University, Linz, 4040, Austria
| | - Stuart S P Parkin
- Nano Systems from Ions, Spins, and Electrons (NISE), Max Planck Institute of Microstructure Physics, 06120, Halle (Saale), Germany
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9
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Liu J, Zhang X, Ji Y, Gao X, Wu J, Zhang M, Li L, Liu X, Yan W, Yao T, Yin Y, Wang L, Guo H, Cheng G, Wang Z, Gao P, Wang Y, Chen K, Liao Z. Controllable Itinerant Ferromagnetism in Weakly Correlated 5d SrIrO 3. J Phys Chem Lett 2022; 13:11946-11954. [PMID: 36534070 DOI: 10.1021/acs.jpclett.2c03313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
The weakly correlated nature of 5d oxide SrIrO3 determines its rare ferromagnetism, and the control of its magnetic order is even less studied. Tailoring structure distortion is currently a main route to tune the magnetic order of 5d iridates, but only for the spatially confined insulating counterparts. Here, we have realized ferromagnetic order in metallic SrIrO3 by construction of SrIrO3/ferromagnetic-insulator (LaCoO3) superlattices, which reveal a giant coercivity of ∼10 T and saturation field of ∼25 T with strong perpendicular magnetic anisotropy. The Curie temperature of SrIrO3 can be controlled by engineering interface charge transfer, which is confirmed by Hall effect measurements collaborating with EELS and XAS. Besides, the noncoplanar spin texture is captured, which is caused by interfacial Dzyaloshinskii-Moriya interactions as well. These results indicate controllable itinerant ferromagnetism and an emergent topological magnetic state in strong spin-orbit coupled semimetal SrIrO3, showing great potential to develop efficient spintronic devices.
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Affiliation(s)
- Junhua Liu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei230026, China
| | - Xinxin Zhang
- International Center for Quantum Materials and Electron Microscopy Laboratory, School of Physics, Peking University, Beijing100871, China
| | - Yaoyao Ji
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei230026, China
| | - Xiaofei Gao
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei230026, China
| | - Jiating Wu
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei230031, China
| | - Minjie Zhang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei230031, China
| | - Lin Li
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei230026, China
| | - Xiaokang Liu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei230026, China
| | - Wensheng Yan
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei230026, China
| | - Tao Yao
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei230026, China
| | - Yuewei Yin
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei230026, China
- Department of Physics and CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, University of Science and Technology of China, Hefei230026, China
| | - Lingfei Wang
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei230026, China
| | - Hangwen Guo
- State Key Laboratory of Surface Physics and Institute for Nanoelectronics Devices and Quantum Computing, Fudan University, Shanghai200433, China
| | - Guanglei Cheng
- CAS Key Laboratory of Microscale Magnetic Resonance and Department of Modern Physics, University of Science and Technology of China, Hefei230026, China
| | - Zhaosheng Wang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei230031, China
| | - Peng Gao
- International Center for Quantum Materials and Electron Microscopy Laboratory, School of Physics, Peking University, Beijing100871, China
| | - Yilin Wang
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei230026, China
| | - Kai Chen
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei230026, China
| | - Zhaoliang Liao
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei230026, China
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10
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Liang J, Chshiev M, Fert A, Yang H. Gradient-Induced Dzyaloshinskii-Moriya Interaction. NANO LETTERS 2022; 22:10128-10133. [PMID: 36520645 DOI: 10.1021/acs.nanolett.2c03973] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
The Dzyaloshinskii-Moriya interaction (DMI) that arises in the magnetic systems with broken inversion symmetry plays an essential role in topological spintronics. Here, by means of atomistic spin calculations, we study an intriguing type of DMI (g-DMI) that emerges in the films with composition gradient. We show that both the strength and chirality of g-DMI can be controlled by the composition gradient even in the disordered system. The layer-resolved analysis of g-DMI unveils its additive nature inside the bulk layers and clarifies the linear thickness dependence of g-DMI observed in experiments. Furthermore, we demonstrate the g-DMI-induced chiral magnetic structures, such as spin spirals and skyrmions, and the g-DMI driven field-free spin-orbit torque (SOT) switching, both of which are crucial toward practical device application. These results elucidate the underlying mechanisms of g-DMI and open up a new way to engineer the topological magnetic textures.
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Affiliation(s)
- Jinghua Liang
- National Laboratory of Solid State Microstructures, School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
| | - Mairbek Chshiev
- Univ. Grenoble Alpes, CEA, CNRS, Spintec, 38000 Grenoble, France
- Institut Universitaire de France, Paris 75231, France
| | - Albert Fert
- Unité Mixte de Physique CNRS-Thales, Université Paris-Saclay, Palaiseau 91767, France
| | - Hongxin Yang
- National Laboratory of Solid State Microstructures, School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
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11
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Tai L, Dai B, Li J, Huang H, Chong SK, Wong KL, Zhang H, Zhang P, Deng P, Eckberg C, Qiu G, He H, Wu D, Xu S, Davydov A, Wu R, Wang KL. Distinguishing the Two-Component Anomalous Hall Effect from the Topological Hall Effect. ACS NANO 2022; 16:17336-17346. [PMID: 36126321 DOI: 10.1021/acsnano.2c08155] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
In transport, the topological Hall effect (THE) presents itself as nonmonotonic features (or humps and dips) in the Hall signal and is widely interpreted as a sign of chiral spin textures, like magnetic skyrmions. However, when the anomalous Hall effect (AHE) is also present, the coexistence of two AHEs could give rise to similar artifacts, making it difficult to distinguish between genuine THE with AHE and two-component AHE. Here, we confirm genuine THE with AHE by means of transport and magneto-optical Kerr effect (MOKE) microscopy, in which magnetic skyrmions are directly observed, and find that genuine THE occurs in the transition region of the AHE. In sharp contrast, the artifact "THE" or two-component AHE occurs well beyond the saturation of the "AHE component" (under the false assumption of THE + AHE). Furthermore, we distinguish artifact "THE" from genuine THE by three methods: (1) minor loops, (2) temperature dependence, and (3) gate dependence. Minor loops of genuine THE with AHE are always within the full loop, while minor loops of the artifact "THE" may reveal a single loop that cannot fit into the "AHE component". In addition, the temperature or gate dependence of the artifact "THE" may also be accompanied by a polarity change of the "AHE component", as the nonmonotonic features vanish, while the temperature dependence of genuine THE with AHE reveals no such change. Our work may help future researchers to exercise caution and use these methods for careful examination in order to ascertain the genuine THE.
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Affiliation(s)
- Lixuan Tai
- Department of Electrical and Computer Engineering, University of California, Los Angeles, California 90095, United States
| | - Bingqian Dai
- Department of Electrical and Computer Engineering, University of California, Los Angeles, California 90095, United States
| | - Jie Li
- Department of Physics and Astronomy, University of California, Irvine, California 92697, United States
| | - Hanshen Huang
- Department of Electrical and Computer Engineering, University of California, Los Angeles, California 90095, United States
| | - Su Kong Chong
- Department of Electrical and Computer Engineering, University of California, Los Angeles, California 90095, United States
| | - Kin L Wong
- Department of Electrical and Computer Engineering, University of California, Los Angeles, California 90095, United States
| | - Huairuo Zhang
- Theiss Research, Inc., La Jolla, California 92037, United States
- Materials Science and Engineering Division, National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899, United States
| | - Peng Zhang
- Department of Electrical and Computer Engineering, University of California, Los Angeles, California 90095, United States
| | - Peng Deng
- Department of Electrical and Computer Engineering, University of California, Los Angeles, California 90095, United States
| | - Christopher Eckberg
- Department of Electrical and Computer Engineering, University of California, Los Angeles, California 90095, United States
- Fibertek, Inc., Herndon, Virginia 20171, United States
- US Army Research Laboratory, Adelphi, Maryland 20783, United States
- US Army Research Laboratory, Playa Vista, California 90094, United States
| | - Gang Qiu
- Department of Electrical and Computer Engineering, University of California, Los Angeles, California 90095, United States
| | - Haoran He
- Department of Electrical and Computer Engineering, University of California, Los Angeles, California 90095, United States
| | - Di Wu
- Department of Electrical and Computer Engineering, University of California, Los Angeles, California 90095, United States
| | - Shijie Xu
- Department of Electrical and Computer Engineering, University of California, Los Angeles, California 90095, United States
- Shanghai Key Laboratory of Special Artificial Microstructure and Pohl Institute of Solid State Physics and School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
| | - Albert Davydov
- Materials Science and Engineering Division, National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899, United States
| | - Ruqian Wu
- Department of Physics and Astronomy, University of California, Irvine, California 92697, United States
| | - Kang L Wang
- Department of Electrical and Computer Engineering, University of California, Los Angeles, California 90095, United States
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12
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Marfoua B, Hong J. Electric field-induced switching of anomalous Nernst conductivity in the 2D MoTe 2/VSe 2 heterostructure. Phys Chem Chem Phys 2022; 24:22523-22530. [PMID: 36107022 DOI: 10.1039/d2cp03011j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Generation of a transverse electric current by a longitudinal charge or heat current is receiving extensive research efforts because of its potential applications in information-processing devices. Therefore, we investigated the electric field-dependent Curie temperature, anomalous Hall conductivity (AHC), and anomalous Nernst conductivity (ANC) of the 2H-MoTe2/1T-VSe2 heterostructure. The MoTe2/VSe2 heterostructure had a Curie temperature of 270 K and the Curie temperature was substantially increased to 355 K under an electric field. We obtained the electric field-induced switching of the AHC in the electron-doped system, whereas no switching was found in the hole-doped system. Also, the electric field-dependent ANC of the MoTe2/VSe2 heterostructure was investigated. The electric field-dependence of the ANC was more prominent in the electron-doped system. We obtained a large ANC of 2.3 A K-1 m-1 when the electric field was applied from VSe2 to MoTe2 layers and this was switched to -0.6 A K-1 m-1 with an opposite electric field. This finding may indicate that the 2D MoTe2/VSe2 heterostructure can be used for potential applications in energy conversion and spintronic devices.
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Affiliation(s)
- Brahim Marfoua
- Department of Physics, Pukyong National University, Busan 608-737, Korea.
| | - Jisang Hong
- Department of Physics, Pukyong National University, Busan 608-737, Korea.
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13
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Jeon JH, Na HR, Kim H, Lee S, Song S, Kim J, Park S, Kim J, Noh H, Kim G, Jerng SK, Chun SH. Emergent Topological Hall Effect from Exchange Coupling in Ferromagnetic Cr 2Te 3/Noncoplanar Antiferromagnetic Cr 2Se 3 Bilayers. ACS NANO 2022; 16:8974-8982. [PMID: 35621270 DOI: 10.1021/acsnano.2c00025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The topological Hall effect has been observed in magnetic materials of complex spin structures or bilayers of trivial magnets and strong spin-orbit-coupled systems. In view of current attention on dissipationless topological electronics, the occurrence of the topological Hall effect in new systems or by an unexpected mechanism is fascinating. Here, we report a robust topological Hall effect generated in bilayers of a ferromagnet and a noncoplanar antiferromagnet, from the interfacial Dzyaloshinskii-Moriya interaction due to the exchange coupling of magnetic layers. Molecular beam epitaxy has been utilized to fabricate heterostructures of a ferromagnetic metal Cr2Te3 and a noncoplanar antiferromagnet Cr2Se3. A significant topological Hall effect at low temperature implies the development of nontrivial spin chirality, and density functional theory calculations explain the correlation of the Dzyaloshinskii-Moriya interaction increase and inversion symmetry breaking at the interface. The presence of noncoplanar ordering in the antiferromagnet plays a pivotal role in producing the topological Hall effect. Our results suggest that the exchange coupling in ferromagnet/noncoplanar antiferromagnet bilayers could be an alternative mechanism toward topologically protected magnetic structures.
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Affiliation(s)
- Jae Ho Jeon
- Department of Physics, Sejong University, Seoul 05006, Korea
| | - Hong Ryeol Na
- Department of Physics, Sejong University, Seoul 05006, Korea
| | - Heeju Kim
- Department of Physics and HMC, Sejong University, Seoul 05006, Korea
| | - Sunghun Lee
- Department of Physics, Sejong University, Seoul 05006, Korea
| | - Sehwan Song
- Department of Physics, Pusan National University, Busan 46241, Korea
| | - Jiwoong Kim
- Department of Physics, Pusan National University, Busan 46241, Korea
| | - Sungkyun Park
- Department of Physics, Pusan National University, Busan 46241, Korea
| | - Jeong Kim
- Department of Electrical Engineering, Sejong University, Seoul 05006, Korea
| | - Hwayong Noh
- Department of Physics, Sejong University, Seoul 05006, Korea
| | - Gunn Kim
- Department of Physics and HMC, Sejong University, Seoul 05006, Korea
| | | | - Seung-Hyun Chun
- Department of Physics, Sejong University, Seoul 05006, Korea
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14
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Niu X, Chen BB, Zhong N, Xiang PH, Duan CG. Topological Hall effect in SrRuO 3thin films and heterostructures. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:244001. [PMID: 35325882 DOI: 10.1088/1361-648x/ac60d0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 03/24/2022] [Indexed: 06/14/2023]
Abstract
Transition metal oxides hold a wide spectrum of fascinating properties endowed by the strong electron correlations. In 4dand 5doxides, exotic phases can be realized with the involvement of strong spin-orbit coupling (SOC), such as unconventional magnetism and topological superconductivity. Recently, topological Hall effects (THEs) and magnetic skyrmions have been uncovered in SrRuO3thin films and heterostructures, where the presence of SOC and inversion symmetry breaking at the interface are believed to play a key role. Realization of magnetic skyrmions in oxides not only offers a platform to study topological physics with correlated electrons, but also opens up new possibilities for magnetic oxides using in the low-power spintronic devices. In this review, we discuss recent observations of THE and skyrmions in the SRO film interfaced with various materials, with a focus on the electric tuning of THE. We conclude with a discussion on the directions of future research in this field.
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Affiliation(s)
- Xu Niu
- Key Laboratory of Polar Materials and Devices (MOE) and Department of Electronics, East China Normal University, Shanghai, 200241, People's Republic of China
| | - Bin-Bin Chen
- Key Laboratory of Polar Materials and Devices (MOE) and Department of Electronics, East China Normal University, Shanghai, 200241, People's Republic of China
| | - Ni Zhong
- Key Laboratory of Polar Materials and Devices (MOE) and Department of Electronics, East China Normal University, Shanghai, 200241, People's Republic of China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi 030006, People's Republic of China
| | - Ping-Hua Xiang
- Key Laboratory of Polar Materials and Devices (MOE) and Department of Electronics, East China Normal University, Shanghai, 200241, People's Republic of China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi 030006, People's Republic of China
| | - Chun-Gang Duan
- Key Laboratory of Polar Materials and Devices (MOE) and Department of Electronics, East China Normal University, Shanghai, 200241, People's Republic of China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi 030006, People's Republic of China
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15
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Takashiro T, Akiyama R, Kibirev IA, Matetskiy AV, Nakanishi R, Sato S, Fukasawa T, Sasaki T, Toyama H, Hiwatari KL, Zotov AV, Saranin AA, Hirahara T, Hasegawa S. Soft-Magnetic Skyrmions Induced by Surface-State Coupling in an Intrinsic Ferromagnetic Topological Insulator Sandwich Structure. NANO LETTERS 2022; 22:881-887. [PMID: 35084202 DOI: 10.1021/acs.nanolett.1c02952] [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
A magnetic skyrmion induced on a ferromagnetic topological insulator (TI) is a real-space manifestation of the chiral spin texture in the momentum space and can be a carrier for information processing by manipulating it in tailored structures. Here, a sandwich structure containing two layers of a self-assembled ferromagnetic septuple-layer TI, Mn(Bi1-xSbx)2Te4 (MnBST), separated by quintuple layers of TI, (Bi1-xSbx)2Te3 (BST), is fabricated and skyrmions are observed through the topological Hall effect in an intrinsic magnetic topological insulator for the first time. The thickness of BST spacer layer is crucial in controlling the coupling between the gapped topological surface states in the two MnBST layers to stabilize the skyrmion formation. The homogeneous, highly ordered arrangement of the Mn atoms in the septuple-layer MnBST leads to a strong exchange interaction therein, which makes the skyrmions "soft magnetic". This would open an avenue toward a topologically robust rewritable magnetic memory.
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Affiliation(s)
- Takuya Takashiro
- Department of Physics, The University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - Ryota Akiyama
- Department of Physics, The University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - Ivan A Kibirev
- Institute of Automation and Control Processes, Vladivostok 690041, Russia
| | - Andrey V Matetskiy
- Institute of Automation and Control Processes, Vladivostok 690041, Russia
| | - Ryosuke Nakanishi
- Department of Physics, The University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - Shunsuke Sato
- Department of Physics, The University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - Takuro Fukasawa
- Department of Physics, Tokyo Institute of Technology, Tokyo 152-8551, Japan
| | - Taisuke Sasaki
- National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
| | - Haruko Toyama
- Department of Physics, The University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - Kota L Hiwatari
- Department of Physics, The University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - Andrey V Zotov
- Institute of Automation and Control Processes, Vladivostok 690041, Russia
| | | | - Toru Hirahara
- Department of Physics, Tokyo Institute of Technology, Tokyo 152-8551, Japan
| | - Shuji Hasegawa
- Department of Physics, The University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
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16
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Li Z, Chen X, Chen Y, Zhang Q, Zhang H, Zhang J, Shi W, He B, Zhang J, Song J, Han F, Liu B, Gu L, Hu F, Chen Y, Shen B, Sun J. Infinite-layer/perovskite oxide heterostructure-induced high-spin states in SrCuO 2/SrRuO 3 bilayer films. MATERIALS HORIZONS 2021; 8:3468-3476. [PMID: 34766611 DOI: 10.1039/d1mh01385h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Heterostructures composed of dissimilar oxides with different properties offer opportunities to develop emergent devices with desired functionalities. A key feature of oxide heterostructures is interface electronics and orbital reconstructions. Here, we combined infinite-layered SrCuO2 and perovskite SrRuO3 into heterostructures. A rare high spin state as large as 3.0 μB f.u-1 and an increase in Curie temperature by 12 K are achieved in an ultrathin SrRuO3 film capped by a SrCuO2 layer. Atomic-scale lattice imaging shows the uniform CuO2-plane-to-RuO5-pyramid connection at the interface, where the regularly arranged RuO5 pyramids were elongated along the out-of-plane direction. As revealed by theoretical calculations and spectral analysis, these features finally result in an abnormally high spin state of the interfacial Ru ions with highly polarized eg orbitals. The present work demonstrates that oxygen coordination engineering at the infinite-layer/perovskite oxide interface is a promising approach towards advanced oxide electronics.
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Affiliation(s)
- Zhe Li
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaobing Chen
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuansha Chen
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Fujian Innovation Academy, Chinese Academy of Sciences, Fuzhou, Fujian 350108, China
| | - Qinghua Zhang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hui Zhang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jine Zhang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenxiao Shi
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Bin He
- Spintronics Institute, School of Physics and Technology, University of Jinan, Jinan 250022, China
| | - Jinxing Zhang
- Department of Physics, Beijing Normal University, Beijing 100875, China
| | - Jinghua Song
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Furong Han
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Banggui Liu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lin Gu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Fengxia Hu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yunzhong Chen
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Baogen Shen
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jirong Sun
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Spintronics Institute, School of Physics and Technology, University of Jinan, Jinan 250022, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, People's Republic of China
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17
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van Thiel TC, Brzezicki W, Autieri C, Hortensius JR, Afanasiev D, Gauquelin N, Jannis D, Janssen N, Groenendijk DJ, Fatermans J, Van Aert S, Verbeeck J, Cuoco M, Caviglia AD. Coupling Charge and Topological Reconstructions at Polar Oxide Interfaces. PHYSICAL REVIEW LETTERS 2021; 127:127202. [PMID: 34597094 DOI: 10.1103/physrevlett.127.127202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 07/21/2021] [Indexed: 06/13/2023]
Abstract
In oxide heterostructures, different materials are integrated into a single artificial crystal, resulting in a breaking of inversion symmetry across the heterointerfaces. A notable example is the interface between polar and nonpolar materials, where valence discontinuities lead to otherwise inaccessible charge and spin states. This approach paved the way for the discovery of numerous unconventional properties absent in the bulk constituents. However, control of the geometric structure of the electronic wave functions in correlated oxides remains an open challenge. Here, we create heterostructures consisting of ultrathin SrRuO_{3}, an itinerant ferromagnet hosting momentum-space sources of Berry curvature, and LaAlO_{3}, a polar wide-band-gap insulator. Transmission electron microscopy reveals an atomically sharp LaO/RuO_{2}/SrO interface configuration, leading to excess charge being pinned near the LaAlO_{3}/SrRuO_{3} interface. We demonstrate through magneto-optical characterization, theoretical calculations and transport measurements that the real-space charge reconstruction drives a reorganization of the topological charges in the band structure, thereby modifying the momentum-space Berry curvature in SrRuO_{3}. Our results illustrate how the topological and magnetic features of oxides can be manipulated by engineering charge discontinuities at oxide interfaces.
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Affiliation(s)
- T C van Thiel
- Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628CJ Delft, Netherlands
| | - W Brzezicki
- International Research Centre Magtop, Institute of Physics, Polish Academy of Sciences, Aleja Lotników 32/46, PL-02668 Warsaw, Poland
- Institute of Theoretical Physics, Jagiellonian University, ulica S. Łojasiewicza 11, PL-30348 Kraków, Poland
| | - C Autieri
- International Research Centre Magtop, Institute of Physics, Polish Academy of Sciences, Aleja Lotników 32/46, PL-02668 Warsaw, Poland
| | - J R Hortensius
- Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628CJ Delft, Netherlands
| | - D Afanasiev
- Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628CJ Delft, Netherlands
| | - N Gauquelin
- Electron Microscopy for Materials Science (EMAT), University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
| | - D Jannis
- Electron Microscopy for Materials Science (EMAT), University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
| | - N Janssen
- Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628CJ Delft, Netherlands
| | - D J Groenendijk
- Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628CJ Delft, Netherlands
| | - J Fatermans
- Electron Microscopy for Materials Science (EMAT), University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
- Imec-Vision Lab, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - S Van Aert
- Electron Microscopy for Materials Science (EMAT), University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
| | - J Verbeeck
- Electron Microscopy for Materials Science (EMAT), University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
| | - M Cuoco
- SPIN-CNR, IT-84084 Fisciano (SA), Italy
- Dipartimento di Fisica "E. R. Caianiello", Università di Salerno, IT-84084 Fisciano (SA), Italy
| | - A D Caviglia
- Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628CJ Delft, Netherlands
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18
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Lu J, Si L, Zhang Q, Tian C, Liu X, Song C, Dong S, Wang J, Cheng S, Qu L, Zhang K, Shi Y, Huang H, Zhu T, Mi W, Zhong Z, Gu L, Held K, Wang L, Zhang J. Defect-Engineered Dzyaloshinskii-Moriya Interaction and Electric-Field-Switchable Topological Spin Texture in SrRuO 3. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2102525. [PMID: 34223676 DOI: 10.1002/adma.202102525] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Indexed: 06/13/2023]
Abstract
In situ electrical control of the Dzyaloshinskii-Moriya interaction (DMI) is one of the central but challenging goals toward skyrmion-based device applications. An atomic design of defective interfaces in spin-orbit-coupled transition-metal oxides can be an appealing strategy to achieve this goal. In this work, by utilizing the distinct formation energies and diffusion barriers of oxygen vacancies at SrRuO3 /SrTiO3 (001), a sharp interface is constructed between oxygen-deficient and stoichiometric SrRuO3 . This interfacial inversion-symmetry breaking leads to a sizable DMI, which can induce skyrmionic magnetic bubbles and the topological Hall effect in a more than 10 unit-cell-thick SrRuO3 . This topological spin texture can be reversibly manipulated through the migration of oxygen vacancies under electric gating. In particular, the topological Hall signal can be deterministically switched ON and OFF. This result implies that the defect-engineered topological spin textures may offer an alternate perspective for future skyrmion-based memristor and synaptic devices.
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Affiliation(s)
- Jingdi Lu
- Department of Physics, Beijing Normal University, Beijing, 100875, China
| | - Liang Si
- Institut für Festkörperphysik, TU Wien, Wiedner Hauptstraße 8-10, Vienna, 1040, Austria
- Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, China
| | - Qinghua Zhang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Science, Beijing, 100190, China
| | - Chengfeng Tian
- Department of Physics, Beijing Normal University, Beijing, 100875, China
| | - Xin Liu
- Department of Physics, Beijing Normal University, Beijing, 100875, China
| | - Chuangye Song
- Department of Physics, Beijing Normal University, Beijing, 100875, China
| | - Shouzhe Dong
- School of Materials Science and Engineering, and Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing, 100081, China
| | - Jie Wang
- Department of Physics, Beijing Normal University, Beijing, 100875, China
| | - Sheng Cheng
- Spallation Neutron Source Science Center, Dongguan, 523803, China
| | - Lili Qu
- Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, 230026, China
| | - Kexuan Zhang
- Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, 230026, China
| | - Youguo Shi
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Science, Beijing, 100190, China
| | - Houbing Huang
- School of Materials Science and Engineering, and Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing, 100081, China
| | - Tao Zhu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Science, Beijing, 100190, China
- Spallation Neutron Source Science Center, Dongguan, 523803, China
| | - Wenbo Mi
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparation Technology, School of Science, Tianjin University, Tianjin, 300354, China
| | - Zhicheng Zhong
- Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, China
| | - Lin Gu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Science, Beijing, 100190, China
| | - Karsten Held
- Institut für Festkörperphysik, TU Wien, Wiedner Hauptstraße 8-10, Vienna, 1040, Austria
| | - Lingfei Wang
- Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, 230026, China
| | - Jinxing Zhang
- Department of Physics, Beijing Normal University, Beijing, 100875, China
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19
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Bhattacharyya S, Akhgar G, Gebert M, Karel J, Edmonds MT, Fuhrer MS. Recent Progress in Proximity Coupling of Magnetism to Topological Insulators. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2007795. [PMID: 34185344 DOI: 10.1002/adma.202007795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 01/11/2021] [Indexed: 05/08/2023]
Abstract
Inducing long-range magnetic order in 3D topological insulators can gap the Dirac-like metallic surface states, leading to exotic new phases such as the quantum anomalous Hall effect or the axion insulator state. These magnetic topological phases can host robust, dissipationless charge and spin currents or unique magnetoelectric behavior, which can be exploited in low-energy electronics and spintronics applications. Although several different strategies have been successfully implemented to realize these states, to date these phenomena have been confined to temperatures below a few Kelvin. This review focuses on one strategy: inducing magnetic order in topological insulators by proximity of magnetic materials, which has the capability for room temperature operation, unlocking the potential of magnetic topological phases for applications. The unique advantages of this strategy, the important physical mechanisms facilitating magnetic proximity effect, and the recent progress to achieve, understand, and harness proximity-coupled magnetic order in topological insulators are discussed. Some emerging new phenomena and applications enabled by proximity coupling of magnetism and topological materials, such as skyrmions and the topological Hall effect, are also highlighted, and the authors conclude with an outlook on remaining challenges and opportunities in the field.
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Affiliation(s)
- Semonti Bhattacharyya
- School of Physics and Astronomy, Monash University, Victoria, 3800, Australia
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Victoria, 3800, Australia
| | - Golrokh Akhgar
- School of Physics and Astronomy, Monash University, Victoria, 3800, Australia
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Victoria, 3800, Australia
| | - Matthew Gebert
- School of Physics and Astronomy, Monash University, Victoria, 3800, Australia
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Victoria, 3800, Australia
| | - Julie Karel
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Victoria, 3800, Australia
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria, 3800, Australia
| | - Mark T Edmonds
- School of Physics and Astronomy, Monash University, Victoria, 3800, Australia
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Victoria, 3800, Australia
| | - Michael S Fuhrer
- School of Physics and Astronomy, Monash University, Victoria, 3800, Australia
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Victoria, 3800, Australia
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20
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Zheng G, Wang M, Zhu X, Tan C, Wang J, Albarakati S, Aloufi N, Algarni M, Farrar L, Wu M, Yao Y, Tian M, Zhou J, Wang L. Tailoring Dzyaloshinskii-Moriya interaction in a transition metal dichalcogenide by dual-intercalation. Nat Commun 2021; 12:3639. [PMID: 34131134 PMCID: PMC8206329 DOI: 10.1038/s41467-021-23658-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 05/07/2021] [Indexed: 11/09/2022] Open
Abstract
Dzyaloshinskii-Moriya interaction (DMI) is vital to form various chiral spin textures, novel behaviors of magnons and permits their potential applications in energy-efficient spintronic devices. Here, we realize a sizable bulk DMI in a transition metal dichalcogenide (TMD) 2H-TaS2 by intercalating Fe atoms, which form the chiral supercells with broken spatial inversion symmetry and also act as the source of magnetic orderings. Using a newly developed protonic gate technology, gate-controlled protons intercalation could further change the carrier density and intensely tune DMI via the Ruderman-Kittel-Kasuya-Yosida mechanism. The resultant giant topological Hall resistivity [Formula: see text] of [Formula: see text] at [Formula: see text] (about [Formula: see text] larger than the zero-bias value) is larger than most known chiral magnets. Theoretical analysis indicates that such a large topological Hall effect originates from the two-dimensional Bloch-type chiral spin textures stabilized by DMI, while the large anomalous Hall effect comes from the gapped Dirac nodal lines by spin-orbit interaction. Dual-intercalation in 2H-TaS2 provides a model system to reveal the nature of DMI in the large family of TMDs and a promising way of gate tuning of DMI, which further enables an electrical control of the chiral spin textures and related electromagnetic phenomena.
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Affiliation(s)
- Guolin Zheng
- School of Science, RMIT University, Melbourne, VIC, 3001, Australia
| | - Maoyuan Wang
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing, 100081, China.,Beijing Key Lab of Nanophotonics & Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing, 100081, China.,International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, China
| | - Xiangde Zhu
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences (CAS), Hefei, 230031, Anhui, China
| | - Cheng Tan
- School of Science, RMIT University, Melbourne, VIC, 3001, Australia
| | - Jie Wang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences (CAS), Hefei, 230031, Anhui, China.,University of Science and Technology of China, Hefei, 230026, Anhui, China
| | | | - Nuriyah Aloufi
- School of Science, RMIT University, Melbourne, VIC, 3001, Australia
| | - Meri Algarni
- School of Science, RMIT University, Melbourne, VIC, 3001, Australia
| | - Lawrence Farrar
- School of Science, RMIT University, Melbourne, VIC, 3001, Australia
| | - Min Wu
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences (CAS), Hefei, 230031, Anhui, China
| | - Yugui Yao
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing, 100081, China.,Beijing Key Lab of Nanophotonics & Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing, 100081, China
| | - Mingliang Tian
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences (CAS), Hefei, 230031, Anhui, China. .,Department of Physics, School of Physics and Materials Science, Anhui University, Hefei, 230601, Anhui, China. .,Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China.
| | - Jianhui Zhou
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences (CAS), Hefei, 230031, Anhui, China.
| | - Lan Wang
- School of Science, RMIT University, Melbourne, VIC, 3001, Australia.
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21
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Real-space observation of ferroelectrically induced magnetic spin crystal in SrRuO 3. Nat Commun 2021; 12:2007. [PMID: 33790268 PMCID: PMC8012650 DOI: 10.1038/s41467-021-22165-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 03/04/2021] [Indexed: 11/25/2022] Open
Abstract
Unusual features in the Hall Resistivity of thin film systems are frequently associated with whirling spin textures such as Skyrmions. A host of recent investigations of Hall Hysteresis loops in SrRuO3 heterostructures have provided conflicting evidence for different causes for such features. We have constructed an SrRuO3-PbTiO3 (Ferromagnetic – Ferroelectric) bilayer that exhibits features in the Hall Hysteresis previously attributed to a Topological Hall Effect, and Skyrmions. Here we show field dependent Magnetic Force Microscopy measurements throughout the key fields where the ‘THE’ presents, revealing the emergence to two periodic, chiral spin textures. The zero-field cycloidal phase, which then transforms into a ‘double-q’ incommensurate spin crystal appears over the appearance of the ‘Topological-like’ Hall effect region, and develop into a ferromagnetic switching regime as the sample reaches saturation, and the ‘Topological-like’ response diminishes. Scanning Tunnelling Electron Microscopy and Density Functional Theory is used to observe and analyse surface inversion symmetry breaking and confirm the role of an interfacial Dzyaloshinskii–Moriya interaction at the heart of the system. There is an ongoing debate in the origin of unusual bumps in the resistive Hall measurements in SrRuO3 systems. Here, the authors analyze surface inversion symmetry breaking and confirm the role of an interfacial Dzyaloshinskii–Moriya interaction at the heart of the system, revealing a magnetic spin crystal emergent across the unusual bumps.
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22
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Zheng D, Fang YW, Zhang S, Li P, Wen Y, Fang B, He X, Li Y, Zhang C, Tong W, Mi W, Bai H, Alshareef HN, Qiu ZQ, Zhang X. Berry Phase Engineering in SrRuO 3/SrIrO 3/SrTiO 3 Superlattices Induced by Band Structure Reconstruction. ACS NANO 2021; 15:5086-5095. [PMID: 33606942 DOI: 10.1021/acsnano.0c10200] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The Berry phase, which reveals the intimate geometrical structure underlying quantum mechanics, plays a central role in the anomalous Hall effect. In this work, we observed a sign change of Berry curvatures at the interface between the ferromagnet SrRuO3 (SRO) layer and the SrIrO3 (SIO) layer with strong spin-orbit coupling. The negative Berry curvature at the interface, induced by the strongly spin-orbit-coupled Ir 5d bands near the Fermi level, makes the SRO/SIO interface different from the SRO layer that has a positive Berry curvature. These opposite Berry curvatures led to two anomalous Hall effect (AHE) channels with opposite signs at the SRO/SIO interface and in the SRO layer, respectively, resulting in a hump-like feature in the Hall resistivity loop. This observation offers a straightforward explanation of the hump-like feature that is usually associated with the chiral magnetic structure or magnetic skyrmions. Hence, this study provides evidence to oppose the widely accepted claim that magnetic skyrmions induce the hump-like feature.
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Affiliation(s)
- Dongxing Zheng
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Processing Technology, Institute of Advanced Materials Physics, Faculty of Science, Tianjin University, Tianjin 300072, China
| | - Yue-Wen Fang
- Laboratory for Materials and Structures & Tokyo Tech World Research Hub Initiative (WRHI), Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, Kanagawa 226-8503, Japan
- NYU-ECNU Institute of Physics, New York University Shanghai, Shanghai 200122, China
| | - Senfu Zhang
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Peng Li
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Yan Wen
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Bin Fang
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Xin He
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Yan Li
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Chenhui Zhang
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Wenyi Tong
- Theoretical Materials Physics, Q-MAT, CESAM, Université de Liège, B-4000 Liège, Belgium
| | - Wenbo Mi
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Processing Technology, Institute of Advanced Materials Physics, Faculty of Science, Tianjin University, Tianjin 300072, China
| | - Haili Bai
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Processing Technology, Institute of Advanced Materials Physics, Faculty of Science, Tianjin University, Tianjin 300072, China
| | - Husam N Alshareef
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Zi Qiang Qiu
- Department of Physics, University of California at Berkeley, Berkeley, California 94720, United States
| | - Xixiang Zhang
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
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23
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Abstract
Skyrmion, a concept originally proposed in particle physics half a century ago, can now find the most fertile field for its applicability, that is, the magnetic skyrmion realized in helimagnetic materials. The spin swirling vortex-like texture of the magnetic skyrmion can define the particle nature by topology; that is, all the constituent spin moments within the two-dimensional sheet wrap the sphere just one time. Such a topological nature of the magnetic skyrmion can lead to extraordinary metastability via topological protection and the driven motion with low electric-current excitation, which may promise future application to spintronics. The skyrmions in the magnetic materials frequently show up as the crystal lattice form, e.g., hexagonal lattice, but sometimes as isolated or independent particles. These skyrmions in magnets were initially found in acentric magnets, such as chiral, polar, and bilayered magnets endowed with antisymmetric spin exchange interaction, while the skyrmion host materials have been explored in a broader family of compounds including centrosymmetric magnets. This review describes the materials science and materials chemistry of magnetic skyrmions using the classification scheme of the skyrmion forming microscopic mechanisms. The emergent phenomena and functions mediated by skyrmions are described, including the generation of emergent magnetic and electric field by statics and dynamics of skrymions and the inherent magnetoelectric effect. The other important magnetic topological defects in two or three dimensions, such as biskyrmions, antiskyrmions, merons, and hedgehogs, are also reviewed in light of their interplay with the skyrmions.
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Affiliation(s)
- Yoshinori Tokura
- Department of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan.,RIKEN Center for Emergent Matter Science (CEMS), Wako, 351-0198, Japan.,Tokyo College, University of Tokyo, Tokyo 113-8656, Japan
| | - Naoya Kanazawa
- Department of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan
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24
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Li Z, Liu X, Jiang J, Mi W, Bai H. Electric field induced reversal of spin polarization, magnetic anisotropy and tailored Dzyaloshinskii-Moriya interaction in underoxidized SrRuO 3/SrTiO 3 heterostructures. Phys Chem Chem Phys 2021; 23:3008-3018. [PMID: 33480932 DOI: 10.1039/d0cp06362b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Electric field tailored magnetic properties of the perovskite-type oxide heterostructures are important in spintronic devices with low energy consumption and small size. Here, the electric field modulated magnetic properties of underoxidized SrRuO3 (SRO)/SrTiO3 (STO) heterostructures are investigated using first-principles calculations. The spin polarization of underoxidized SRO/STO heterostructures turns from negative to positive as the electric field changes from -0.2 to 0.2 V nm-1. The underoxidized SRO/STO heterostructure with 7 SRO atomic layers turns from perpendicular magnetic anisotropy to in-plane magnetic anisotropy as the electric field turns from -0.2 to 0.2 V nm-1, which can be attributed to the in-plane dx2-y2 and out-of-plane dxz, dyz orbitals. The Dzyaloshinskii-Moriya interaction of underoxidized SRO/STO heterostructures can also be effectively tailored using an electric field. These results indicate that the use of electric field is an effective method to modulate magnetic properties of perovskite-type oxide heterostructures, which is beneficial for the development of the high-performance spintronic devices.
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Affiliation(s)
- Zengjie Li
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparation Technology, School of Science, Tianjin University, Tianjin 300354, China.
| | - Xiang Liu
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparation Technology, School of Science, Tianjin University, Tianjin 300354, China.
| | - Jiawei Jiang
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparation Technology, School of Science, Tianjin University, Tianjin 300354, China.
| | - Wenbo Mi
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparation Technology, School of Science, Tianjin University, Tianjin 300354, China.
| | - Haili Bai
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparation Technology, School of Science, Tianjin University, Tianjin 300354, China.
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25
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Chen S, Yuan S, Hou Z, Tang Y, Zhang J, Wang T, Li K, Zhao W, Liu X, Chen L, Martin LW, Chen Z. Recent Progress on Topological Structures in Ferroic Thin Films and Heterostructures. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2000857. [PMID: 32815214 DOI: 10.1002/adma.202000857] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 04/17/2020] [Indexed: 06/11/2023]
Abstract
Topological spin/polarization structures in ferroic materials continue to draw great attention as a result of their fascinating physical behaviors and promising applications in the field of high-density nonvolatile memories as well as future energy-efficient nanoelectronic and spintronic devices. Such developments have been made, in part, based on recent advances in theoretical calculations, the synthesis of high-quality thin films, and the characterization of their emergent phenomena and exotic phases. Herein, progress over the last decade in the study of topological structures in ferroic thin films and heterostructures is explored, including the observation of topological structures and control of their structures and emergent physical phenomena through epitaxial strain, layer thickness, electric, magnetic fields, etc. First, the evolution of topological spin structures (e.g., magnetic skyrmions) and associated functionalities (e.g., topological Hall effect) in magnetic thin films and heterostructures is discussed. Then, the exotic polar topologies (e.g., domain walls, closure domains, polar vortices, bubble domains, and polar skyrmions) and their emergent physical properties in ferroelectric oxide films and heterostructures are explored. Finally, a brief overview and prospectus of how the field may evolve in the coming years is provided.
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Affiliation(s)
- Shanquan Chen
- School of Materials Science and Engineering, Harbin Institute of Technology, Shenzhen, 518055, China
| | - Shuai Yuan
- School of Materials Science and Engineering, Harbin Institute of Technology, Shenzhen, 518055, 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, P. R. China
- National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou, 510006, P. R. China
| | - Yunlong Tang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang, 110016, China
| | - Jinping Zhang
- School of Materials Science and Engineering, Harbin Institute of Technology, Shenzhen, 518055, China
| | - Tao Wang
- School of Materials Science and Engineering, Harbin Institute of Technology, Shenzhen, 518055, China
| | - Kang Li
- Flexible Printed Electronics Technology Center, Harbin Institute of Technology, Shenzhen, 518055, China
| | - Weiwei Zhao
- School of Materials Science and Engineering, Harbin Institute of Technology, Shenzhen, 518055, China
- Flexible Printed Electronics Technology Center, Harbin Institute of Technology, Shenzhen, 518055, China
| | - Xingjun Liu
- School of Materials Science and Engineering, Harbin Institute of Technology, Shenzhen, 518055, China
| | - Lang Chen
- Department of Physics, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Lane W Martin
- Department of Materials Science and Engineering, University of California, Berkeley, CA, 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Zuhuang Chen
- School of Materials Science and Engineering, Harbin Institute of Technology, Shenzhen, 518055, China
- Flexible Printed Electronics Technology Center, Harbin Institute of Technology, Shenzhen, 518055, China
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26
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Interface-induced sign reversal of the anomalous Hall effect in magnetic topological insulator heterostructures. Nat Commun 2021; 12:79. [PMID: 33397964 PMCID: PMC7782489 DOI: 10.1038/s41467-020-20349-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Accepted: 11/27/2020] [Indexed: 11/19/2022] Open
Abstract
The Berry phase picture provides important insights into the electronic properties of condensed matter systems. The intrinsic anomalous Hall (AH) effect can be understood as the consequence of non-zero Berry curvature in momentum space. Here, we fabricate TI/magnetic TI heterostructures and find that the sign of the AH effect in the magnetic TI layer can be changed from being positive to negative with increasing the thickness of the top TI layer. Our first-principles calculations show that the built-in electric fields at the TI/magnetic TI interface influence the band structure of the magnetic TI layer, and thus lead to a reconstruction of the Berry curvature in the heterostructure samples. Based on the interface-induced AH effect with a negative sign in TI/V-doped TI bilayer structures, we create an artificial “topological Hall effect”-like feature in the Hall trace of the V-doped TI/TI/Cr-doped TI sandwich heterostructures. Our study provides a new route to create the Berry curvature change in magnetic topological materials that may lead to potential technological applications. Berry curvature connects to exotic electronic phases hence it provides important insights to understand quantum materials. Here, the authors report sign change of the anomalous Hall effect resulted from Berry curvature change at the interface of a topological insulator/magnetic topological insulator heterostructure.
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27
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Huang H, Lee SJ, Kim B, Sohn B, Kim C, Kao CC, Lee JS. Detection of the Chiral Spin Structure in Ferromagnetic SrRuO 3 Thin Film. ACS APPLIED MATERIALS & INTERFACES 2020; 12:37757-37763. [PMID: 32696641 DOI: 10.1021/acsami.0c10545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
SrRuO3 (SRO) thin films and their heterostructure have attracted much attention because of the recently demonstrated fascinating properties, such as topological Hall effect and skyrmions. Critical to the understanding of those SRO properties is the study of the spin configuration. Here, we conduct resonant soft X-ray scattering (RSXS) at the oxygen K edge to investigate the spin configuration of a four-unit-cell SRO film that was grown epitaxially on a single-crystal SrTiO3. The RSXS signal under a magnetic field (∼0.4 tesla) clearly shows a magnetic dichroism pattern around the specular reflection. Model calculations on the RSXS signal demonstrate that the magnetic dichroism pattern originates from a Néel-type chiral spin structure in this SRO thin film. We believe that the observed spin structure of the SRO system is a critical piece of information for understanding its intriguing magnetic and transport properties.
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Affiliation(s)
- Hai Huang
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Sang-Jun Lee
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Bongju Kim
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, South Korea
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, South Korea
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Byungmin Sohn
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, South Korea
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, South Korea
| | - Changyoung Kim
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, South Korea
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, South Korea
| | - Chi-Chang Kao
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Jun-Sik Lee
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
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28
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Kim WJ, Oh T, Song J, Ko EK, Li Y, Mun J, Kim B, Son J, Yang Z, Kohama Y, Kim M, Yang BJ, Noh TW. Strain engineering of the magnetic multipole moments and anomalous Hall effect in pyrochlore iridate thin films. SCIENCE ADVANCES 2020; 6:eabb1539. [PMID: 32832638 PMCID: PMC7439458 DOI: 10.1126/sciadv.abb1539] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 05/29/2020] [Indexed: 05/31/2023]
Abstract
The recent observation of the anomalous Hall effect (AHE) without notable magnetization in antiferromagnets has suggested that ferromagnetic ordering is not a necessary condition. Thus, recent theoretical studies have proposed that higher-rank magnetic multipoles formed by clusters of spins (cluster multipoles) can generate the AHE without magnetization. Despite such an intriguing proposal, controlling the unconventional AHE by inducing these cluster multipoles has not been investigated. Here, we demonstrate that strain can manipulate the hidden Berry curvature effect by inducing the higher-rank cluster multipoles in spin-orbit-coupled antiferromagnets. Observing the large AHE on fully strained antiferromagnetic Nd2Ir2O7 thin films, we prove that strain-induced cluster T 1-octupoles are the only source of observed AHE. Our results provide a previously unidentified pathway for generating the unconventional AHE via strain-induced magnetic structures and establish a platform for exploring undiscovered topological phenomena via strain in correlated materials.
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Affiliation(s)
- Woo Jin Kim
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
| | - Taekoo Oh
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
- Center for Theoretical Physics (CTP), Seoul National University, Seoul 08826, Republic of Korea
| | - Jeongkeun Song
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
| | - Eun Kyo Ko
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
| | - Yangyang Li
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
| | - Junsik Mun
- Department of Materials Science and Engineering and Research Institute of Advanced Materials, Seoul National University, Seoul 08826, Republic of Korea
| | - Bongju Kim
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
| | - Jaeseok Son
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
| | - Zhuo Yang
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Yoshimitsu Kohama
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Miyoung Kim
- Department of Materials Science and Engineering and Research Institute of Advanced Materials, Seoul National University, Seoul 08826, Republic of Korea
| | - Bohm-Jung Yang
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
- Center for Theoretical Physics (CTP), Seoul National University, Seoul 08826, Republic of Korea
| | - Tae Won Noh
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
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29
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Jiang J, Xiao D, Wang F, Shin JH, Andreoli D, Zhang J, Xiao R, Zhao YF, Kayyalha M, Zhang L, Wang K, Zang J, Liu C, Samarth N, Chan MHW, Chang CZ. Concurrence of quantum anomalous Hall and topological Hall effects in magnetic topological insulator sandwich heterostructures. NATURE MATERIALS 2020; 19:732-737. [PMID: 32015537 DOI: 10.1038/s41563-020-0605-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 01/03/2020] [Indexed: 05/08/2023]
Abstract
The quantum anomalous Hall (QAH) effect is a consequence of non-zero Berry curvature in momentum space. The QAH insulator harbours dissipation-free chiral edge states in the absence of an external magnetic field. However, the topological Hall (TH) effect, a hallmark of chiral spin textures, is a consequence of real-space Berry curvature. Here, by inserting a topological insulator (TI) layer between two magnetic TI layers, we realized the concurrence of the TH effect and the QAH effect through electric-field gating. The TH effect is probed by bulk carriers, whereas the QAH effect is characterized by chiral edge states. The appearance of the TH effect in the QAH insulating regime is a consequence of chiral magnetic domain walls that result from the gate-induced Dzyaloshinskii-Moriya interaction and occurs during the magnetization reversal process in the magnetic TI sandwich samples. The coexistence of chiral edge states and chiral spin textures provides a platform for proof-of-concept dissipationless spin-textured spintronic applications.
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Affiliation(s)
- Jue Jiang
- Department of Physics, The Pennsylvania State University, University Park, PA, USA
| | - Di Xiao
- Department of Physics, The Pennsylvania State University, University Park, PA, USA
| | - Fei Wang
- Department of Physics, The Pennsylvania State University, University Park, PA, USA
| | - Jae-Ho Shin
- Department of Physics, The Pennsylvania State University, University Park, PA, USA
| | | | - Jianxiao Zhang
- Department of Physics, The Pennsylvania State University, University Park, PA, USA
| | - Run Xiao
- Department of Physics, The Pennsylvania State University, University Park, PA, USA
| | - Yi-Fan Zhao
- Department of Physics, The Pennsylvania State University, University Park, PA, USA
| | - Morteza Kayyalha
- Department of Physics, The Pennsylvania State University, University Park, PA, USA
| | - Ling Zhang
- Department of Physics, The Pennsylvania State University, University Park, PA, USA
| | - Ke Wang
- Materials Research Institute, The Pennsylvania State University, University Park, PA, USA
| | - Jiadong Zang
- Department of Physics, University of New Hampshire, Durham, NH, USA
| | - Chaoxing Liu
- Department of Physics, The Pennsylvania State University, University Park, PA, USA
| | - Nitin Samarth
- Department of Physics, The Pennsylvania State University, University Park, PA, USA.
| | - Moses H W Chan
- Department of Physics, The Pennsylvania State University, University Park, PA, USA.
| | - Cui-Zu Chang
- Department of Physics, The Pennsylvania State University, University Park, PA, USA.
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30
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Wang W, Sun W, Zhang G, Ren F, Wang Y, You C, Cheng Z. Ferroelectrically tunable magnetism in BiFeO 3/BaTiO 3 heterostructure revealed by the first-principles calculations. J Adv Res 2020; 24:371-377. [PMID: 32477607 PMCID: PMC7248427 DOI: 10.1016/j.jare.2020.04.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Revised: 04/22/2020] [Accepted: 04/23/2020] [Indexed: 12/02/2022] Open
Abstract
The perovskite oxide interface has attracted extensive attention as a platform for achieving strong coupling between ferroelectricity and magnetism. In this work, robust control of magnetoelectric (ME) coupling in the BiFeO3/BaTiO3 (BFO/BTO) heterostructure (HS) was revealed by using the first-principles calculation. Switching of the ferroelectric polarization of BTO induce large ME effect with significant changes on the magnetic ordering and easy magnetization axis, making up for the weak ME coupling effect of single-phase multiferroic BFO. In addition, the Dzyaloshinskii-Moriya interaction (DMI) and the exchange coupling constants J for the BFO part of the HSs are simultaneously manipulated by the ferroelectric polarization, especially the DMI at the interface is significantly enhanced, which is three or four times larger than that of the individual BFO bulk. This work paves the way for designing new nanomagnetic devices based on the substantial interfacial ME effect.
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Affiliation(s)
- Wenxuan Wang
- Institute for Computational Materials Science, School of Physics and Electronics, Henan University, Kaifeng 475004, People’s Republic of China
| | - Wei Sun
- Institute for Computational Materials Science, School of Physics and Electronics, Henan University, Kaifeng 475004, People’s Republic of China
| | - Guangbiao Zhang
- Institute for Computational Materials Science, School of Physics and Electronics, Henan University, Kaifeng 475004, People’s Republic of China
| | - Fengzhu Ren
- Institute for Computational Materials Science, School of Physics and Electronics, Henan University, Kaifeng 475004, People’s Republic of China
| | - Yuanxu Wang
- Institute for Computational Materials Science, School of Physics and Electronics, Henan University, Kaifeng 475004, People’s Republic of China
- National Demonstration Center for Experimental Physics and Electronics Education, School of Physics, Henan University, Kaifeng 475004, People’s Republic of China
| | - Caiyin You
- School of Materials Science & Engineering, Xi’an University of Technology, Xi’an 710048, People’s Republic of China
| | - Zhenxiang Cheng
- Institute for Computational Materials Science, School of Physics and Electronics, Henan University, Kaifeng 475004, People’s Republic of China
- Institute for Superconducting & Electronic Materials, Australian Institute of Innovative Materials, University of Wollongong, Innovation Campus, Squires Way, North Wollongong, NSW 2500, Australia
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31
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Plettenberg J, Stier M, Thorwart M. Steering of the Skyrmion Hall Angle by Gate Voltages. PHYSICAL REVIEW LETTERS 2020; 124:207202. [PMID: 32501073 DOI: 10.1103/physrevlett.124.207202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 02/28/2020] [Accepted: 04/17/2020] [Indexed: 06/11/2023]
Abstract
Magnetic skyrmions can be driven by an applied spin-polarized electron current that exerts a spin-transfer torque on the localized spins constituting the skyrmion. However, the longitudinal dynamics is plagued by the skyrmion Hall effect, which causes the skyrmions to acquire a transverse velocity component. We show how to use spin-orbit interaction to control the skyrmion Hall angle and how the interplay of spin-transfer and spin-orbit torques can lead to a complete suppression of the transverse motion. Since the spin-orbit torques can be controlled all electronically by a gate voltage, the skyrmion motion can be steered all electronically on a broad racetrack at high speed and conceptually new writing and gating operations can be realized.
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Affiliation(s)
- J Plettenberg
- I. Institut für Theoretische Physik, Universität Hamburg, Jungiusstraße 9, 20355 Hamburg, Germany
| | - M Stier
- I. Institut für Theoretische Physik, Universität Hamburg, Jungiusstraße 9, 20355 Hamburg, Germany
| | - M Thorwart
- I. Institut für Theoretische Physik, Universität Hamburg, Jungiusstraße 9, 20355 Hamburg, Germany
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32
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Wang L, Feng Q, Lee HG, Ko EK, Lu Q, Noh TW. Controllable Thickness Inhomogeneity and Berry Curvature Engineering of Anomalous Hall Effect in SrRuO 3 Ultrathin Films. NANO LETTERS 2020; 20:2468-2477. [PMID: 32202801 DOI: 10.1021/acs.nanolett.9b05206] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In quantum matters hosting electron-electron correlation and spin-orbit coupling, spatial inhomogeneities, arising from competing ground states, can be essential for understanding exotic topological properties. A prominent example is Hall anomalies observed in SrRuO3 films, which were interpreted in terms of either magnetic skyrmion-induced topological Hall effect or inhomogeneous anomalous Hall effect (AHE). To clarify this ambiguity, we systematically investigated the evolution of AHE with controllable inhomogeneities in SrRuO3 film thickness (tSRO). By exploiting the step-flow growth of SrRuO3 films, we induced a microscopically ordered stripe pattern with one-unit-cell differences in tSRO. The associated spatial distribution of momentum-space Berry curvatures enables a two-channel AHE with hump-like Hall anomalies, which can be continuously engineered according to non-integer tSRO. We further microscopically characterized the stripe-like ferromagnetic domains and two-step magnetic switching behavior in the inhomogeneous SrRuO3 film. These unique features can be utilized to identify the two-channel AHE model and understand its microscopic origin.
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Affiliation(s)
- Lingfei Wang
- Center for Correlated Electron Systems (CCES), Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
| | - Qiyuan Feng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Han Gyeol Lee
- Center for Correlated Electron Systems (CCES), Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
| | - Eun Kyo Ko
- Center for Correlated Electron Systems (CCES), Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
| | - Qingyou Lu
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
- Hefei National Laboratory for Physical Sciences at the Microscale and Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Tae Won Noh
- Center for Correlated Electron Systems (CCES), Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
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33
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Wysocki L, Schöpf J, Ziese M, Yang L, Kovács A, Jin L, Versteeg RB, Bliesener A, Gunkel F, Kornblum L, Dittmann R, van Loosdrecht PHM, Lindfors-Vrejoiu I. Electronic Inhomogeneity Influence on the Anomalous Hall Resistivity Loops of SrRuO 3 Epitaxially Interfaced with 5d Perovskites. ACS OMEGA 2020; 5:5824-5833. [PMID: 32226862 PMCID: PMC7097901 DOI: 10.1021/acsomega.9b03996] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Accepted: 02/05/2020] [Indexed: 06/10/2023]
Abstract
SrRuO3, a 4d ferromagnet with multiple Weyl nodes at the Fermi level, offers a rich playground to design epitaxial heterostructures and superlattices with fascinating magnetic and magnetotransport properties. Interfacing ultrathin SrRuO3 layers with large spin-orbit coupling 5d transition-metal oxides, such as SrIrO3, results in pronounced peaklike anomalies in the magnetic field dependence of the Hall resistivity. Such anomalies have been attributed either to the formation of Néel-type skyrmions or to modifications of the Berry curvature of the topologically nontrivial conduction bands near the Fermi level of SrRuO3. Here, epitaxial multilayers based on SrRuO3 interfaced with 5d perovskite oxides, such as SrIrO3 and SrHfO3, were studied. This work focuses on the magnetotransport properties of the multilayers, aiming to unravel the role played by the interfaces with 5d perovskites in the peaklike anomalies of the Hall resistance loops of SrRuO3 layers. Interfacing with large band gap insulating SrHfO3 layers did not influence the anomalous Hall resistance loops, while interfacing with the nominally paramagnetic semimetal SrIrO3 resulted in pronounced peaklike anomalies, which have been lately attributed to a topological Hall effect contribution as a result of skyrmions. This interpretation is, however, under strong debate and lately alternative causes, such as inhomogeneity of the thickness and the electronic properties of the SrRuO3 layers, have been considered. Aligned with these latter proposals, our findings reveal the central role played in the anomalies of the Hall resistivity loops by electronic inhomogeneity of SrRuO3 layers due to the interfacing with semimetallic 5d5 SrIrO3.
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Affiliation(s)
- Lena Wysocki
- Institute
of Physics II, University of Cologne, 50937 Cologne, Germany
| | - Jörg Schöpf
- Institute
of Physics II, University of Cologne, 50937 Cologne, Germany
| | - Michael Ziese
- Felix
Bloch Institute for Solid State Physics, University of Leipzig, 04109 Leipzig, Germany
| | - Lin Yang
- Institute
of Physics II, University of Cologne, 50937 Cologne, Germany
| | - András Kovács
- Ernst
Ruska-Centre for Microscopy and Spectroscopy with Electrons, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Lei Jin
- Ernst
Ruska-Centre for Microscopy and Spectroscopy with Electrons, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Rolf B. Versteeg
- Institute
of Physics II, University of Cologne, 50937 Cologne, Germany
| | - Andrea Bliesener
- Institute
of Physics II, University of Cologne, 50937 Cologne, Germany
| | - Felix Gunkel
- PGI-7, Forschungszentrum
Jülich, 52428 Jülich, Germany
- Institute
of Electronic Materials (IWE2), RWTH Aachen
University, 52062 Aachen, Germany
| | - Lior Kornblum
- Andrew &
Erna Viterbi Department of Electrical Engineering, Technion—Israel Institute of Technology, 3200003 Haifa, Israel
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34
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Li D, Huang X, Xiao Z, Chen H, Zhang L, Hao Y, Song J, Shao DF, Tsymbal EY, Lu Y, Hong X. Polar coupling enabled nonlinear optical filtering at MoS 2/ferroelectric heterointerfaces. Nat Commun 2020; 11:1422. [PMID: 32184400 PMCID: PMC7078226 DOI: 10.1038/s41467-020-15191-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Accepted: 02/14/2020] [Indexed: 11/09/2022] Open
Abstract
Complex oxide heterointerfaces and van der Waals heterostructures present two versatile but intrinsically different platforms for exploring emergent quantum phenomena and designing new functionalities. The rich opportunity offered by the synergy between these two classes of materials, however, is yet to be charted. Here, we report an unconventional nonlinear optical filtering effect resulting from the interfacial polar alignment between monolayer MoS2 and a neighboring ferroelectric oxide thin film. The second harmonic generation response at the heterointerface is either substantially enhanced or almost entirely quenched by an underlying ferroelectric domain wall depending on its chirality, and can be further tailored by the polar domains. Unlike the extensively studied coupling mechanisms driven by charge, spin, and lattice, the interfacial tailoring effect is solely mediated by the polar symmetry, as well explained via our density functional theory calculations, pointing to a new material strategy for the functional design of nanoscale reconfigurable optical applications.
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Affiliation(s)
- Dawei Li
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, NE, 68588-0299, USA
| | - Xi Huang
- Department of Electrical and Computer Engineering, University of Nebraska-Lincoln, Lincoln, NE, 68588-0511, USA
| | - Zhiyong Xiao
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, NE, 68588-0299, USA
| | - Hanying Chen
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, NE, 68588-0299, USA
| | - Le Zhang
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, NE, 68588-0299, USA
| | - Yifei Hao
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, NE, 68588-0299, USA
| | - Jingfeng Song
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, NE, 68588-0299, USA
| | - Ding-Fu Shao
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, NE, 68588-0299, USA
| | - Evgeny Y Tsymbal
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, NE, 68588-0299, USA.,Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, NE, 68588-0298, USA
| | - Yongfeng Lu
- Department of Electrical and Computer Engineering, University of Nebraska-Lincoln, Lincoln, NE, 68588-0511, USA. .,Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, NE, 68588-0298, USA.
| | - Xia Hong
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, NE, 68588-0299, USA. .,Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, NE, 68588-0298, USA.
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35
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Lux FR, Freimuth F, Blügel S, Mokrousov Y. Chiral Hall Effect in Noncollinear Magnets from a Cyclic Cohomology Approach. PHYSICAL REVIEW LETTERS 2020; 124:096602. [PMID: 32202897 DOI: 10.1103/physrevlett.124.096602] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 12/22/2019] [Accepted: 02/06/2020] [Indexed: 06/10/2023]
Abstract
We demonstrate the emergence of an anomalous Hall effect in chiral magnetic textures which is neither proportional to the net magnetization nor to the well-known emergent magnetic field that is responsible for the topological Hall effect. Instead, it appears already at linear order in the gradients of the magnetization texture and exists for one-dimensional magnetic textures such as domain walls and spin spirals. It receives a natural interpretation in the language of Alain Connes' noncommutative geometry. We show that this chiral Hall effect resembles the familiar topological Hall effect in essential properties while its phenomenology is distinctly different. Our findings make the reinterpretation of experimental data necessary, and offer an exciting twist in engineering the electrical transport through magnetic skyrmions.
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Affiliation(s)
- Fabian R Lux
- Peter Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, 52425 Jülich, Germany
- Department of Physics, RWTH Aachen University, 52056 Aachen, Germany
| | - Frank Freimuth
- Peter Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, 52425 Jülich, Germany
| | - Stefan Blügel
- Peter Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, 52425 Jülich, Germany
| | - Yuriy Mokrousov
- Peter Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, 52425 Jülich, Germany
- Institute of Physics, Johannes Gutenberg University Mainz, 55099 Mainz, Germany
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36
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Gu Y, Song C, Zhang Q, Li F, Tan H, Xu K, Li J, Saleem MS, Fayaz MU, Peng J, Hu F, Gu L, Liu W, Zhang Z, Pan F. Interfacial Control of Ferromagnetism in Ultrathin SrRuO 3 Films Sandwiched between Ferroelectric BaTiO 3 Layers. ACS APPLIED MATERIALS & INTERFACES 2020; 12:6707-6715. [PMID: 31927907 DOI: 10.1021/acsami.9b20941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Interfaces between materials provide an intellectually rich arena for fundamental scientific discovery and device design. However, the frustration of magnetization and conductivity of perovskite oxide films under reduced dimensionality is detrimental to their device performance, preventing their active low-dimensional application. Herein, by inserting the ultrathin 4d ferromagnetic SrRuO3 layer between ferroelectric BaTiO3 layers to form a sandwich heterostructure, we observe enhanced physical properties in ultrathin SrRuO3 films, including longitudinal conductivity, Curie temperature, and saturated magnetic moment. Especially, the saturated magnetization can be enhanced to ∼3.12 μB/Ru in ultrathin BaTiO3/SrRuO3/BaTiO3 trilayers, which is beyond the theoretical limit of bulk value (2 μB/Ru). This observation is attributed to the synergistic ferroelectric proximity effect (SFPE) at upper and lower BaTiO3/SrRuO3 heterointerfaces, as revealed by the high-resolution lattice structure analysis. This SFPE in dual-ferroelectric interface cooperatively induces ferroelectric-like lattice distortions in RuO6 oxygen octahedra and subsequent spin-state crossover in SrRuO3, which in turn accounts for the observed enhanced magnetization. Besides the fundamental significance of interface-induced spin-lattice coupling, our findings also provide a viable route to the electrical control of magnetic ordering, taking a step toward low-power applications in all-oxide spintronics.
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Affiliation(s)
- Youdi Gu
- Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering , Tsinghua University , Beijing 100084 , China
- Shenyang National Laboratory for Materials Science , Institute of Metal Research, University of Chinese Academy of Sciences, Chinese Academy of Sciences , Shenyang 110016 , China
| | - Cheng Song
- Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering , Tsinghua University , Beijing 100084 , China
| | - Qinghua Zhang
- Beijing National Laboratory for Condensed Matter Physics , Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences , Beijing 100190 , China
| | - Fan Li
- Max Planck Institute for Microstructure Physics , Halle (Saale) D-06120 , Germany
| | - Hengxin Tan
- Max Planck Institute for Microstructure Physics , Halle (Saale) D-06120 , Germany
| | - Kun Xu
- National Center for Electron Microscopy in Beijing, School of Materials Science and Engineering , Tsinghua University , Beijing 100084 , China
| | - Jia Li
- Beijing National Laboratory for Condensed Matter Physics , Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences , Beijing 100190 , China
| | - Muhammad Shahrukh Saleem
- Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering , Tsinghua University , Beijing 100084 , China
| | - Muhammad Umer Fayaz
- Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering , Tsinghua University , Beijing 100084 , China
| | - Jingjing Peng
- Beijing Institute of Aeronautical Materials , Beijing 100095 , China
| | - Fengxia Hu
- Beijing National Laboratory for Condensed Matter Physics , Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences , Beijing 100190 , China
| | - Lin Gu
- Beijing National Laboratory for Condensed Matter Physics , Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences , Beijing 100190 , China
| | - Wei Liu
- Shenyang National Laboratory for Materials Science , Institute of Metal Research, University of Chinese Academy of Sciences, Chinese Academy of Sciences , Shenyang 110016 , China
| | - Zhidong Zhang
- Shenyang National Laboratory for Materials Science , Institute of Metal Research, University of Chinese Academy of Sciences, Chinese Academy of Sciences , Shenyang 110016 , China
| | - Feng Pan
- Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering , Tsinghua University , Beijing 100084 , China
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37
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Lee HG, Wang L, Si L, He X, Porter DG, Kim JR, Ko EK, Kim J, Park SM, Kim B, Wee ATS, Bombardi A, Zhong Z, Noh TW. Atomic-Scale Metal-Insulator Transition in SrRuO 3 Ultrathin Films Triggered by Surface Termination Conversion. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e1905815. [PMID: 31830343 DOI: 10.1002/adma.201905815] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 11/12/2019] [Indexed: 06/10/2023]
Abstract
The metal-insulator transition (MIT) in transition-metal-oxide is fertile ground for exploring intriguing physics and potential device applications. Here, an atomic-scale MIT triggered by surface termination conversion in SrRuO3 ultrathin films is reported. Uniform and effective termination engineering at the SrRuO3 (001) surface can be realized via a self-limiting water-leaching process. As the surface termination converts from SrO to RuO2 , a highly insulating and nonferromagnetic phase emerges within the topmost SrRuO3 monolayer. Such a spatially confined MIT is corroborated by systematic characterizations on electrical transport, magnetism, and scanning tunneling spectroscopy. Density functional theory calculations and X-ray linear dichroism further suggest that the surface termination conversion breaks the local octahedral symmetry of the crystal field. The resultant modulation in 4d orbital occupancy stabilizes a nonferromagnetic insulating surface state. This work introduces a new paradigm to stimulate and tune exotic functionalities of oxide heterostructures with atomic precision.
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Affiliation(s)
- Han Gyeol Lee
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Republic of Korea
| | - Lingfei Wang
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Republic of Korea
| | - Liang Si
- Key Laboratory of Magnetic Materials and Devices & 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
- Institut für Festkörperphysik, Vienna, 1040, Austria
| | - Xiaoyue He
- Department of Physics, National University of Singapore, Singapore, 117542, Singapore
- Songshan Lake Materials Laboratory, Dongguan, 523808, P. R. China
| | - Daniel G Porter
- Diamond Light Source Ltd., Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE, UK
| | - Jeong Rae Kim
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Republic of Korea
| | - Eun Kyo Ko
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jinkwon Kim
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Republic of Korea
| | - Sung Min Park
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Republic of Korea
| | - Bongju Kim
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Republic of Korea
| | - Andrew Thye Shen Wee
- Department of Physics, National University of Singapore, Singapore, 117542, Singapore
| | - Alessandro Bombardi
- Diamond Light Source Ltd., Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE, UK
| | - Zhicheng Zhong
- Key Laboratory of Magnetic Materials and Devices & 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
- China Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Tae Won Noh
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Republic of Korea
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38
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Gupta R, Bhatti IN, Pramanik AK. Site dilution and charge disorder effect on physical properties in SrRu 1-x Ga x O 3. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:035803. [PMID: 31574499 DOI: 10.1088/1361-648x/ab49a1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Here, we report an evolution of structural, magnetic and transport behavior in doped SrRu1-x Ga x O3 (x [Formula: see text] 0.2). The nonmagnetic dopant Ga3+ (3d 10) not only acts for magnetic site dilution in SrRuO3 but also modifies the Ru charge state and electronic density. Our studies show that Ga3+ substitution does not affect the original orthorhombic- Pbnm structure of SrRuO3 which is due to its matching ionic radii with Ru4+ . However, Ga3+ has a substantial effect on the magnetic behavior of SrRuO3 where it decreases both magnetic moment as well as magnetic transition temperature [Formula: see text]. Further, this dilution induces Griffiths phase behavior across [Formula: see text] and cluster-glass behavior at low temperature with higher concentration of doping. The magnetic critical exponent [Formula: see text] increases with x due to this site dilution effect. The Ga3+ induces an insulating state in SrRuO3 with x > 0.05. The charge transport in paramagnetic as well as in insulating state of samples can be well described with Mott's modified variable-range-hopping model. The metallic charge transport just below [Formula: see text] in SrRuO3 obeys Fermi liquid behavior which breaks down at low temperature. We further find a correlation between field dependent magnetoresistance and magnetization through power-law behavior over the series.
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Affiliation(s)
- Renu Gupta
- School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
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39
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Li Z, Shen S, Tian Z, Hwangbo K, Wang M, Wang Y, Bartram FM, He L, Lyu Y, Dong Y, Wan G, Li H, Lu N, Zang J, Zhou H, Arenholz E, He Q, Yang L, Luo W, Yu P. Reversible manipulation of the magnetic state in SrRuO 3 through electric-field controlled proton evolution. Nat Commun 2020; 11:184. [PMID: 31924767 PMCID: PMC6954193 DOI: 10.1038/s41467-019-13999-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Accepted: 11/29/2019] [Indexed: 11/09/2022] Open
Abstract
Ionic substitution forms an essential pathway to manipulate the structural phase, carrier density and crystalline symmetry of materials via ion-electron-lattice coupling, leading to a rich spectrum of electronic states in strongly correlated systems. Using the ferromagnetic metal SrRuO3 as a model system, we demonstrate an efficient and reversible control of both structural and electronic phase transformations through the electric-field controlled proton evolution with ionic liquid gating. The insertion of protons results in a large structural expansion and increased carrier density, leading to an exotic ferromagnetic to paramagnetic phase transition. Importantly, we reveal a novel protonated compound of HSrRuO3 with paramagnetic metallic as ground state. We observe a topological Hall effect at the boundary of the phase transition due to the proton concentration gradient across the film-depth. We envision that electric-field controlled protonation opens up a pathway to explore novel electronic states and material functionalities in protonated material systems.
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Affiliation(s)
- Zhuolu Li
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, 100084, Beijing, China
| | - Shengchun Shen
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, 100084, Beijing, China
| | - Zijun Tian
- Key Laboratory of Artificial Structures and Quantum Control, School of Physics and Astronomy and Institute of Natural Sciences, Shanghai Jiao Tong University, 200240, Shanghai, China
| | - Kyle Hwangbo
- Department of Physics, University of Toronto, Toronto, ON, M5S 1A7, Canada
| | - Meng Wang
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, 100084, Beijing, China
| | - Yujia Wang
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, 100084, Beijing, China
| | - F Michael Bartram
- Department of Physics, University of Toronto, Toronto, ON, M5S 1A7, Canada
| | - Liqun He
- Department of Physics, University of Toronto, Toronto, ON, M5S 1A7, Canada
| | - Yingjie Lyu
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, 100084, Beijing, China
| | - Yongqi Dong
- Advanced Photon Source, Argonne National Lab, Argonne, IL, 60439, USA
- Materials Science Division, Argonne National Lab, Argonne, IL, 60439, USA
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, 230026, Hefei, Anhui, China
| | - Gang Wan
- Materials Science Division, Argonne National Lab, Argonne, IL, 60439, USA
| | - Haobo Li
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, 100084, Beijing, China
| | - Nianpeng Lu
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, 100084, Beijing, China
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Science, 100190, Beijing, China
| | - Jiadong Zang
- Department of Physics and Astronomy, University of New Hampshire, Durham, NH, 03824, USA
| | - Hua Zhou
- Advanced Photon Source, Argonne National Lab, Argonne, IL, 60439, USA
| | - Elke Arenholz
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Qing He
- Department of Physics, Durham University, Durham, DH13LE, United Kingdom
| | - Luyi Yang
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, 100084, Beijing, China.
- Department of Physics, University of Toronto, Toronto, ON, M5S 1A7, Canada.
- Frontier Science Center for Quantum Information, 100084, Beijing, China.
| | - Weidong Luo
- Key Laboratory of Artificial Structures and Quantum Control, School of Physics and Astronomy and Institute of Natural Sciences, Shanghai Jiao Tong University, 200240, Shanghai, China.
- Collaborative Innovation Center of Advanced Microstructures, 210093, Nanjing, China.
| | - Pu Yu
- State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, 100084, Beijing, China.
- Frontier Science Center for Quantum Information, 100084, Beijing, China.
- RIKEN Center for Emergent Matter Science (CEMS), Wako, 351-198, Japan.
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40
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Ruan Y, Huang L, Yang Y, Xu G, Zhong K, Huang Z, Zhang JM. Robustness of the electronic structure and charge transfer in topological insulator Bi2Te2Se and Bi2Se2Te thin films under an external electric field. Phys Chem Chem Phys 2020; 22:3867-3874. [DOI: 10.1039/c9cp06206h] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The electronic structure and charge transfer of Bi2Te2Se and Bi2Se2Te thin films are robust to an external electrical field.
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Affiliation(s)
- Yurong Ruan
- Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials
- College of Physics and Energy
- Fujian Normal University
- Fuzhou 350117
- China
| | - Lu Huang
- Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials
- College of Physics and Energy
- Fujian Normal University
- Fuzhou 350117
- China
| | - Yanmin Yang
- Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials
- College of Physics and Energy
- Fujian Normal University
- Fuzhou 350117
- China
| | - Guigui Xu
- Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials
- College of Physics and Energy
- Fujian Normal University
- Fuzhou 350117
- China
| | - Kehua Zhong
- Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials
- College of Physics and Energy
- Fujian Normal University
- Fuzhou 350117
- China
| | - Zhigao Huang
- Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials
- College of Physics and Energy
- Fujian Normal University
- Fuzhou 350117
- China
| | - Jian-Min Zhang
- Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials
- College of Physics and Energy
- Fujian Normal University
- Fuzhou 350117
- China
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41
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Jiang HB, Liu Y, Liu J, Li SY, Song YY, Han DD, Ren LQ. Moisture-Responsive Graphene Actuators Prepared by Two-Beam Laser Interference of Graphene Oxide Paper. Front Chem 2019; 7:464. [PMID: 31316973 PMCID: PMC6610323 DOI: 10.3389/fchem.2019.00464] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2019] [Accepted: 06/11/2019] [Indexed: 12/31/2022] Open
Abstract
Here, we reported an ingenious fabrication of moisture responsive graphene-based actuator via unilateral two-beam laser interference (TBLI) treatment of graphene oxide (GO) papers. TBLI technique has been recognized as a representative photoreduction and patterning strategy for hierarchical structuring of GO. The GO paper can be reduced and cut into grating-like periodic reduced graphene oxide (RGO) microstructures due to laser ablation effect. However, the lower light transmittance of the thick GO paper and the corresponding thermal relaxation phenomenon make it impossible to trigger complete reduction, leading to the formation of the anisotropic GO/reduced GO (RGO) bilayer structure. Interestingly, the RGO side that feature lower OCGs and higher roughness shows strong water adsorption due to the formation of micronanostructures. Due to the different water adsorption capacities of the two sides, a flower moisture-responsive actuator has been fabricated, which exhibits “opening” and “closing” behavior under different humidity conditions.
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Affiliation(s)
- Hao-Bo Jiang
- Key Laboratory of Bionic Engineering (Ministry of Education), Jilin University, Changchun, China
| | - Yan Liu
- Key Laboratory of Bionic Engineering (Ministry of Education), Jilin University, Changchun, China
| | - Juan Liu
- Key Laboratory of Bionic Engineering (Ministry of Education), Jilin University, Changchun, China
| | - Shu-Yi Li
- Key Laboratory of Bionic Engineering (Ministry of Education), Jilin University, Changchun, China
| | - Yun-Yun Song
- Key Laboratory of Bionic Engineering (Ministry of Education), Jilin University, Changchun, China
| | - Dong-Dong Han
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun, China
| | - Lu-Quan Ren
- Key Laboratory of Bionic Engineering (Ministry of Education), Jilin University, Changchun, China
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42
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Avci CO, Rosenberg E, Caretta L, Büttner F, Mann M, Marcus C, Bono D, Ross CA, Beach GSD. Interface-driven chiral magnetism and current-driven domain walls in insulating magnetic garnets. NATURE NANOTECHNOLOGY 2019; 14:561-566. [PMID: 30936554 DOI: 10.1038/s41565-019-0421-2] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 03/06/2019] [Indexed: 05/12/2023]
Abstract
Magnetic oxides exhibit rich fundamental physics1-4 and technologically desirable properties for spin-based memory, logic and signal transmission5-7. Recently, spin-orbit-induced spin transport phenomena have been realized in insulating magnetic oxides by using proximate heavy metal layers such as platinum8-10. In their metallic ferromagnet counterparts, such interfaces also give rise to a Dzyaloshinskii-Moriya interaction11-13 that can stabilize homochiral domain walls and skyrmions with efficient current-driven dynamics. However, chiral magnetism in centrosymmetric oxides has not yet been observed. Here we discover chiral magnetism that allows for pure spin-current-driven domain wall motion in the most ubiquitous class of magnetic oxides, ferrimagnetic iron garnets. We show that epitaxial rare-earth iron garnet films with perpendicular magnetic anisotropy exhibit homochiral Néel domain walls that can be propelled faster than 800 m s-1 by spin current from an adjacent platinum layer. We find that, despite the relatively small interfacial Dzyaloshinskii-Moriya interaction, very high velocities can be attained due to the antiferromagnetic spin dynamics associated with ferrimagnetic order.
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Affiliation(s)
- Can Onur Avci
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Ethan Rosenberg
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Lucas Caretta
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Felix Büttner
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Maxwell Mann
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Colin Marcus
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - David Bono
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Caroline A Ross
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Geoffrey S D Beach
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
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43
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Meng KY, Ahmed AS, Baćani M, Mandru AO, Zhao X, Bagués N, Esser BD, Flores J, McComb DW, Hug HJ, Yang F. Observation of Nanoscale Skyrmions in SrIrO 3/SrRuO 3 Bilayers. NANO LETTERS 2019; 19:3169-3175. [PMID: 30935207 DOI: 10.1021/acs.nanolett.9b00596] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Skyrmion imaging and electrical detection via topological Hall (TH) effect are two primary techniques for probing magnetic skyrmions, which hold promise for next-generation magnetic storage. However, these two kinds of complementary techniques have rarely been employed to investigate the same samples. We report the observation of nanoscale skyrmions in SrIrO3/SrRuO3 (SIO/SRO) bilayers in a wide temperature range from 10 to 100 K. The SIO/SRO bilayers exhibit a remarkable TH effect, which is up to 200% larger than the anomalous Hall (AH) effect at 5 K, and zero-field TH effect at 90 K. Using variable-temperature, high-field magnetic force microscopy (MFM), we imaged skyrmions as small as 10 nm, which emerge in the same field ranges as the TH effect. These results reveal a rich space for skyrmion exploration and tunability in oxide heterostructures.
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Affiliation(s)
- Keng-Yuan Meng
- Department of Physics , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Adam S Ahmed
- Department of Physics , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Mirko Baćani
- Empa , Swiss Federal Laboratories for Materials Science and Technology , Dübendorf CH-8600 , Switzerland
| | - Andrada-Oana Mandru
- Empa , Swiss Federal Laboratories for Materials Science and Technology , Dübendorf CH-8600 , Switzerland
| | - Xue Zhao
- Empa , Swiss Federal Laboratories for Materials Science and Technology , Dübendorf CH-8600 , Switzerland
| | - Núria Bagués
- Center for Electron Microscopy and Analysis , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Bryan D Esser
- Center for Electron Microscopy and Analysis , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Jose Flores
- Department of Physics , The Ohio State University , Columbus , Ohio 43210 , United States
| | - David W McComb
- Center for Electron Microscopy and Analysis , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Hans J Hug
- Empa , Swiss Federal Laboratories for Materials Science and Technology , Dübendorf CH-8600 , Switzerland
- Department of Physics , University of Basel , Basel CH-4056 , Switzerland
| | - Fengyuan Yang
- Department of Physics , The Ohio State University , Columbus , Ohio 43210 , United States
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44
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Qin Q, Liu L, Lin W, Shu X, Xie Q, Lim Z, Li C, He S, Chow GM, Chen J. Emergence of Topological Hall Effect in a SrRuO 3 Single Layer. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1807008. [PMID: 30614567 DOI: 10.1002/adma.201807008] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 12/11/2018] [Indexed: 06/09/2023]
Abstract
Topological Hall effect (THE), appearing as bumps and/or dips in the Hall resistance curves, is considered as a hallmark of the skyrmion spin texture originated from the inversion symmetry breaking and spin-orbit interaction. Recently, Néel-type skyrmion is proposed based on the observed THE in 5d transition metal oxides heterostructures such as SrRuO3 /SrIrO3 bilayers, where the interfacial Dzyaloshinskii-Moriya interaction (DMI), due to the strong spin-orbit coupling (SOC) in SrIrO3 and the broken inversion symmetry at the interface, is believed to play a significant role. Here the emergence of THE in SrRuO3 single layers with thickness ranging from 3 to 6 nm is experimentally demonstrated. It is found that the oxygen octahedron rotation in SrRuO3 also has a significant effect on the observed THE. Furthermore, the THE may be continuously tuned by an applied electrical field. It is proposed that the large SOC of Ru ions together with the broken inversion symmetry, mainly from the interface, produce the DMI that is responsible for the observed THE. The emergence of the gate-tunable DMI in SrRuO3 single layer may stimulate further investigations of new spin-orbit physics in strong SOC oxides.
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Affiliation(s)
- Qing Qin
- Department of Materials Science and Engineering, National University of Singapore, Singapore, 117575, Singapore
| | - Liang Liu
- Department of Materials Science and Engineering, National University of Singapore, Singapore, 117575, Singapore
| | - Weinan Lin
- Department of Materials Science and Engineering, National University of Singapore, Singapore, 117575, Singapore
| | - Xinyu Shu
- Department of Materials Science and Engineering, National University of Singapore, Singapore, 117575, Singapore
| | - Qidong Xie
- Department of Materials Science and Engineering, National University of Singapore, Singapore, 117575, Singapore
| | - Zhishiuh Lim
- NUSNNI-Nanocore, National University of Singapore, Singapore, 117411, Singapore
| | - Changjian Li
- Department of Materials Science and Engineering, National University of Singapore, Singapore, 117575, Singapore
| | - Shikun He
- Data Storage Institute, Agency for Science, Technology and Research (A*STAR), Singapore, 138634, Singapore
| | - Gan Moog Chow
- Department of Materials Science and Engineering, National University of Singapore, Singapore, 117575, Singapore
| | - Jingsheng Chen
- Department of Materials Science and Engineering, National University of Singapore, Singapore, 117575, Singapore
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45
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Wang L, Feng Q, Kim Y, Kim R, Lee KH, Pollard SD, Shin YJ, Zhou H, Peng W, Lee D, Meng W, Yang H, Han JH, Kim M, Lu Q, Noh TW. Ferroelectrically tunable magnetic skyrmions in ultrathin oxide heterostructures. NATURE MATERIALS 2018; 17:1087-1094. [PMID: 30397313 DOI: 10.1038/s41563-018-0204-4] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 09/21/2018] [Indexed: 06/08/2023]
Abstract
Magnetic skyrmions are topologically protected whirling spin texture. Their nanoscale dimensions, topologically protected stability and solitonic nature, together are promising for future spintronics applications. To translate these compelling features into practical spintronic devices, a key challenge lies in achieving effective control of skyrmion properties, such as size, density and thermodynamic stability. Here, we report the discovery of ferroelectrically tunable skyrmions in ultrathin BaTiO3/SrRuO3 bilayer heterostructures. The ferroelectric proximity effect at the BaTiO3/SrRuO3 heterointerface triggers a sizeable Dzyaloshinskii-Moriya interaction, thus stabilizing robust skyrmions with diameters less than a hundred nanometres. Moreover, by manipulating the ferroelectric polarization of the BaTiO3 layer, we achieve local, switchable and nonvolatile control of both skyrmion density and thermodynamic stability. This ferroelectrically tunable skyrmion system can simultaneously enhance the integratability and addressability of skyrmion-based functional devices.
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Affiliation(s)
- Lingfei Wang
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, Republic of Korea.
- Department of Physics and Astronomy, Seoul National University, Seoul, Republic of Korea.
| | - Qiyuan Feng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui, China
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui, China
| | - Yoonkoo Kim
- Department of Materials Science and Engineering and Research Institute of Advanced Materials, Seoul National University, Seoul, Republic of Korea
| | - Rokyeon Kim
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, Republic of Korea
| | - Ki Hoon Lee
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, Republic of Korea
| | - Shawn D Pollard
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore
| | - Yeong Jae Shin
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, Republic of Korea
| | - Haibiao Zhou
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, Republic of Korea
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui, China
| | - Wei Peng
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, Republic of Korea
| | - Daesu Lee
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, Republic of Korea
| | - Wenjie Meng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui, China
| | - Hyunsoo Yang
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore
| | - Jung Hoon Han
- Department of Physics, Sungkyunkwan University, Suwon, Republic of Korea
| | - Miyoung Kim
- Department of Materials Science and Engineering and Research Institute of Advanced Materials, Seoul National University, Seoul, Republic of Korea
| | - Qingyou Lu
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui, China.
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui, China.
| | - Tae Won Noh
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul, Republic of Korea.
- Department of Physics and Astronomy, Seoul National University, Seoul, Republic of Korea.
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46
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Matsuno J, Fujioka J, Okuda T, Ueno K, Mizokawa T, Katsufuji T. Strongly correlated oxides for energy harvesting. SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 2018; 19:899-908. [PMID: 31001365 PMCID: PMC6454405 DOI: 10.1080/14686996.2018.1529524] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Revised: 09/25/2018] [Accepted: 09/25/2018] [Indexed: 06/09/2023]
Abstract
We review recent advances in strongly correlated oxides as thermoelectric materials in pursuit of energy harvesting. We discuss two topics: one is the enhancement of the ordinary thermoelectric properties by controlling orbital degrees of freedom and orbital fluctuation not only in bulk but also at the interface of correlated oxides. The other topic is the use of new phenomena driven by spin-orbit coupling (SOC) of materials. In 5d electron oxides, we show some SOC-related transport phenomena, which potentially contribute to energy harvesting. We outline the current status and a future perspective of oxides as thermoelectric materials.
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Affiliation(s)
- Jobu Matsuno
- Department of Physics, Osaka University, Osaka, Japan
- Center for Emergent Matter Science (CEMS), RIKEN, Saitama, Japan
- PRESTO, Japan Science and Technology Agency, Kawaguchi, Saitama, Japan
| | - Jun Fujioka
- PRESTO, Japan Science and Technology Agency, Kawaguchi, Saitama, Japan
- Department of Applied Physics, University of Tokyo, Tokyo, Japan
- Graduate School of Pure and Applied Science, University of Tsukuba, Tsukuba, Japan
| | - Tetsuji Okuda
- Graduate School of Science and Engineering, Kagoshima University, Kagoshima, Japan
| | - Kazunori Ueno
- Department of Basic Science, University of Tokyo, Tokyo, Japan
| | | | - Takuro Katsufuji
- Department of Physics, Waseda University, Tokyo, Japan
- Kagami Memorial Laboratory for Material Science and Technology, Waseda University, Tokyo, Japan
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47
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Ado IA, Qaiumzadeh A, Duine RA, Brataas A, Titov M. Asymmetric and Symmetric Exchange in a Generalized 2D Rashba Ferromagnet. PHYSICAL REVIEW LETTERS 2018; 121:086802. [PMID: 30192599 DOI: 10.1103/physrevlett.121.086802] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 06/05/2018] [Indexed: 06/08/2023]
Abstract
Dzyaloshinskii-Moriya interaction (DMI) is investigated in a 2D ferromagnet (FM) with spin-orbit interaction of Rashba type at finite temperatures. The FM is described in the continuum limit by an effective s-d model with arbitrary dependence of spin-orbit coupling (SOC) and kinetic energy of itinerant electrons on the absolute value of momentum. In the limit of weak SOC, we derive a general expression for the DMI constant D from a microscopic analysis of the electronic grand potential. We compare D with the exchange stiffness A and show that, to the leading order in small SOC strength α_{R}, the conventional relation D=(4mα_{R}/ℏ)A, in general, does not hold beyond the Bychkov-Rashba model. Moreover, in this model, both A and D vanish at zero temperature in the metal regime (i.e., when two spin sub-bands are partly occupied). For nonparabolic bands or nonlinear Rashba coupling, these coefficients are finite and acquire a nontrivial dependence on the chemical potential that demonstrates the possibility to control the size and chirality of magnetic textures by adjusting a gate voltage.
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Affiliation(s)
- I A Ado
- Radboud University, Institute for Molecules and Materials, NL-6525 AJ Nijmegen, Netherlands
| | - A Qaiumzadeh
- Center for Quantum Spintronics, Department of Physics, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
- Department of Physics, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran
| | - R A Duine
- Center for Quantum Spintronics, Department of Physics, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
- Institute for Theoretical Physics and Centre for Extreme Matter and Emergent Phenomena, Utrecht University, 3584 CE Utrecht, Netherlands
- Department of Applied Physics, Eindhoven University of Technology, Post Office Box 513, 5600 MB Eindhoven, Netherlands
| | - A Brataas
- Center for Quantum Spintronics, Department of Physics, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - M Titov
- Radboud University, Institute for Molecules and Materials, NL-6525 AJ Nijmegen, Netherlands
- ITMO University, Saint Petersburg 197101, Russia
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