1
|
Su SH, Huang TT, Pan BR, Lee JC, Qiu YJ, Chuang PY, Gultom P, Cheng CM, Chen YC, Huang JCA. Large Tunable Spin-to-Charge Conversion in Ni 80Fe 20/Molybdenum Disulfide by Cu Insertion. ACS Appl Mater Interfaces 2024; 16. [PMID: 38670928 PMCID: PMC11082844 DOI: 10.1021/acsami.4c03360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 04/12/2024] [Accepted: 04/18/2024] [Indexed: 04/28/2024]
Abstract
Spin-to-charge conversion at the interface between magnetic materials and transition metal dichalcogenides has drawn great interest in the research efforts to develop fast and ultralow power consumption devices for spintronic applications. Here, we report room temperature observations of spin-to-charge conversion arising from the interface of Ni80Fe20 (Py) and molybdenum disulfide (MoS2). This phenomenon can be characterized by the inverse Edelstein effect length (λIEE), which is enhanced with decreasing MoS2 thicknesses, demonstrating the dominant role of spin-orbital coupling (SOC) in MoS2. The spin-to-charge conversion can be significantly improved by inserting a Cu interlayer between Py and MoS2, suggesting that the Cu interlayer can prevent magnetic proximity effect from the Py layer and protect the SOC on the MoS2 surface from exchange interactions with Py. Furthermore, the Cu-MoS2 interface can enhance the spin current and improve electronic transport. Our results suggest that tailoring the interface of magnetic heterostructures provides an alternative strategy for the development of spintronic devices to achieve higher spin-to-charge conversion efficiencies.
Collapse
Affiliation(s)
- Shu Hsuan. Su
- Department
of Physics, National Cheng Kung University, Tainan 701, Taiwan
| | - Tzu Tai Huang
- Department
of Physics, National Cheng Kung University, Tainan 701, Taiwan
| | - Bi-Rong Pan
- Department
of Physics, National Cheng Kung University, Tainan 701, Taiwan
| | - Jung-Chuan Lee
- Department
of Physics, National Cheng Kung University, Tainan 701, Taiwan
- Sheng
Chuang Technology Company, Taichung 407330, Taiwan
| | - Yi Jie Qiu
- Department
of Physics, National Cheng Kung University, Tainan 701, Taiwan
| | - Pei-Yu Chuang
- National
Synchrotron Radiation Research Center, Hsinchu 300, Taiwan
| | - Pangihutan Gultom
- Department
of Physics, National Cheng Kung University, Tainan 701, Taiwan
| | - Cheng-Maw Cheng
- National
Synchrotron Radiation Research Center, Hsinchu 300, Taiwan
- Department
of Photonics, National Sun Yat-sen University, Kaohsiung 80424, Taiwan
| | - Yi-Chun Chen
- Department
of Physics, National Cheng Kung University, Tainan 701, Taiwan
| | - Jung-Chung Andrew Huang
- Department
of Physics, National Cheng Kung University, Tainan 701, Taiwan
- Department
of Applied Physics, National University
of Kaohsiung, Kaohsiung 811726, Taiwan
- Taiwan Consortium
of Emergent Crystalline Materials, Ministry
of Science and Technology, Taipei 106, Taiwan
| |
Collapse
|
2
|
Shan WY. Gate-tunable circular phonon dichroism effect in bilayer graphene. iScience 2024; 27:109374. [PMID: 38510119 PMCID: PMC10951653 DOI: 10.1016/j.isci.2024.109374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 01/30/2024] [Accepted: 02/27/2024] [Indexed: 03/22/2024] Open
Abstract
Circular phonon dichroism effect has been proposed in two-dimensional materials; however, the lack of tunability hinders the exploration of the effect. Here, we investigate the role of dual-gating-induced inversion symmetry breaking in the circular phonon dichroism effect in bilayer graphene. We find that the introduction of inversion symmetry breaking modifies the response in the layer-symmetric and layer-antisymmetric channels, and results in the occurrence of phonon dichroism in the cross-channel. In the layer representation, the inversion symmetry breaking breaks the equality of intralayer circular phonon dichroism and enhances the interlayer response. Our results suggest that layer degree of freedom provides possibilities to tune phonon dynamics, which paves a way toward different physics and applications of two-dimensional acoustoelectronics and layertronics.
Collapse
Affiliation(s)
- Wen-Yu Shan
- Department of Physics, School of Physics and Materials Science, Guangzhou University, Guangzhou 510006, China
| |
Collapse
|
3
|
Qian Z, Ji J, Qian L, Mao Y, Yao S, Xu J, Wang L. Interlayer coupling controlled electronic and magnetic properties of two-dimensional VOCl 2/PtTe 2 van der Waals heterostructure. RSC Adv 2023; 13:35018-35025. [PMID: 38046632 PMCID: PMC10690494 DOI: 10.1039/d3ra07237a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 11/26/2023] [Indexed: 12/05/2023] Open
Abstract
The coupling of hetero monolayers into van der Waals (vdW) heterostructures has become an effective way to obtain tunable physical and chemical properties of two dimensional (2D) materials. In this work, based on first principles calculations, we systematically explore the electronic and magnetic properties of a 2D VOCl2/PtTe2 heterostructure. Our results indicate that the ground state of the VOCl2/PtTe2 heterostructure is a ferromagnetic (FM) metal with large magnetic anisotropy energy, among which, the VOCl2 "sublayer" shows FM half metallic properties while the PtTe2 "sublayer" shows nonmagnetic metallic properties. The Curie temperature (TC) of VOCl2/PtTe2 is 111 K. Moreover, the FM-antiferromagnetic (AFM) phase transition can be obtained under biaxial strain. Our work provides an effective way to improve the performance of 2D monolayers in nano-electronic devices.
Collapse
Affiliation(s)
- Zhonghua Qian
- College of Physics Science and Technology & Microelectronics Industry Research Institute, Yangzhou University Yangzhou 225002 China
| | - Jie Ji
- College of Physics Science and Technology & Microelectronics Industry Research Institute, Yangzhou University Yangzhou 225002 China
| | - Liyan Qian
- College of Physics Science and Technology & Microelectronics Industry Research Institute, Yangzhou University Yangzhou 225002 China
| | - Yuxuan Mao
- College of Physics Science and Technology & Microelectronics Industry Research Institute, Yangzhou University Yangzhou 225002 China
| | - Suchen Yao
- College of Physics Science and Technology & Microelectronics Industry Research Institute, Yangzhou University Yangzhou 225002 China
| | - Jingyi Xu
- College of Physics Science and Technology & Microelectronics Industry Research Institute, Yangzhou University Yangzhou 225002 China
| | - Licheng Wang
- College of Physics Science and Technology & Microelectronics Industry Research Institute, Yangzhou University Yangzhou 225002 China
| |
Collapse
|
4
|
Lan P, Miao N, Gan Y, Peng L, Han S, Zhou J, Sun Z. High-Throughput Computational Design of 2D Ternary Chalcogenides for Sustainable Energy. J Phys Chem Lett 2023; 14:10489-10498. [PMID: 37967465 DOI: 10.1021/acs.jpclett.3c02486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2023]
Abstract
Two-dimensional materials are considered to be promising for next-generation electronic and energy devices. However, the limited availability of 2D materials hinders their applications. Herein, we employed high-throughput computation to discover new 2D materials by cleaving the bulk and to investigate their electronic, thermoelectric, and optoelectronic properties. Using our database containing 810 structures of chalcogenides ABX3 (A or B = Al, Ga, In, Si, Ge, Sn, P, As, Sb, and Bi; X = S, Se, and Te), we identified 204 new 2D compounds promising for experimental preparation according to the exfoliation energy. Notably, 96 of them are more easily exfoliated than graphene, 52 compounds show higher Seebeck coefficients than Bi2Te3 at 300 K, and 20 compounds have power factors beyond 2 × 10-3 Wm-1 K-2 at 900 K. Also, 6 new compounds exhibit high theoretical photovoltaic efficiency exceeding 30%. Our findings expand the 2D materials family and provide new 2D compounds for sustainable thermoelectric and optoelectronic energy applications.
Collapse
Affiliation(s)
- Penghua Lan
- School of Materials Science and Engineering, Beihang University, Beijing 100191, China
| | - Naihua Miao
- School of Materials Science and Engineering, Beihang University, Beijing 100191, China
| | - Yu Gan
- School of Materials Science and Engineering, Beihang University, Beijing 100191, China
| | - Liyu Peng
- School of Materials Science and Engineering, Beihang University, Beijing 100191, China
| | - Siyu Han
- School of Materials Science and Engineering, Beihang University, Beijing 100191, China
| | - Jian Zhou
- School of Materials Science and Engineering, Beihang University, Beijing 100191, China
| | - Zhimei Sun
- School of Materials Science and Engineering, Beihang University, Beijing 100191, China
| |
Collapse
|
5
|
Victor RT, Marroquin JFR, Safeer SH, Dugato DA, Archanjo BS, Sampaio LC, Garcia F, Felix JF. Automated mechanical exfoliation technique: a spin pumping study in YIG/TMD heterostructures. Nanoscale Horiz 2023; 8:1568-1576. [PMID: 37671742 DOI: 10.1039/d3nh00137g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/07/2023]
Abstract
Spintronics devices rely on the generation and manipulation of spin currents. Two-dimensional transition-metal dichalcogenides (TMDs) are among the most promising materials for a spin current generation due to a lack of inversion symmetry at the interface with the magnetic material. Here, we report on the fabrication of Yttrium Iron Garnet(YIG)/TMD heterostructures by means of a crude and fast method. While the magnetic insulator single-crystalline YIG thin films were grown by magnetron sputtering, the TMDs, namely MoS2 and MoSe2, were directly deposited onto YIG films using an automated mechanical abrasion method. Despite the brute force aspect of the method, it produces high-quality interfaces, which are suitable for spintronic device applications. The spin current density and the effective spin mixing conductance were measured by ferromagnetic resonance, whose values found are among the highest reported in the literature. Our method can be scaled to produce ferromagnetic materials/TMD heterostructures on a large scale, further advancing their potential for practical applications.
Collapse
Affiliation(s)
- Rodrigo Torrão Victor
- Centro Brasileiro de Pesquisas Físicas, rua Dr Xavier Sigaud, 150, Urca, Rio de Janeiro, RJ, 22.290-180, Brazil.
| | | | - Syed Hamza Safeer
- Centro Brasileiro de Pesquisas Físicas, rua Dr Xavier Sigaud, 150, Urca, Rio de Janeiro, RJ, 22.290-180, Brazil.
| | - Danian Alexandre Dugato
- Centro Brasileiro de Pesquisas Físicas, rua Dr Xavier Sigaud, 150, Urca, Rio de Janeiro, RJ, 22.290-180, Brazil.
| | - Braulio Soares Archanjo
- Materials Metrology Division, National Institute of Metrology, Quality, and Technology (INMETRO), Duque de Caxias, Rio de Janeiro, 25.250-020, Brazil
| | - Luiz Carlos Sampaio
- Centro Brasileiro de Pesquisas Físicas, rua Dr Xavier Sigaud, 150, Urca, Rio de Janeiro, RJ, 22.290-180, Brazil.
| | - Flavio Garcia
- Centro Brasileiro de Pesquisas Físicas, rua Dr Xavier Sigaud, 150, Urca, Rio de Janeiro, RJ, 22.290-180, Brazil.
| | - Jorlandio Francisco Felix
- Nucleo de Física Aplicada, Instituto de Física, Universidade de Brasília, Brasília, DF 70910-900, Brazil.
| |
Collapse
|
6
|
Hung CM, Dang DTX, Chanda A, Detellem D, Alzahrani N, Kapuruge N, Pham YTH, Liu M, Zhou D, Gutierrez HR, Arena DA, Terrones M, Witanachchi S, Woods LM, Srikanth H, Phan MH. Enhanced Magnetism and Anomalous Hall Transport through Two-Dimensional Tungsten Disulfide Interfaces. Nanomaterials (Basel) 2023; 13:nano13040771. [PMID: 36839139 PMCID: PMC9967397 DOI: 10.3390/nano13040771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/14/2023] [Accepted: 02/16/2023] [Indexed: 05/14/2023]
Abstract
The magnetic proximity effect (MPE) has recently been explored to manipulate interfacial properties of two-dimensional (2D) transition metal dichalcogenide (TMD)/ferromagnet heterostructures for use in spintronics and valleytronics. However, a full understanding of the MPE and its temperature and magnetic field evolution in these systems is lacking. In this study, the MPE has been probed in Pt/WS2/BPIO (biphase iron oxide, Fe3O4 and α-Fe2O3) heterostructures through a comprehensive investigation of their magnetic and transport properties using magnetometry, four-probe resistivity, and anomalous Hall effect (AHE) measurements. Density functional theory (DFT) calculations are performed to complement the experimental findings. We found that the presence of monolayer WS2 flakes reduces the magnetization of BPIO and hence the total magnetization of Pt/WS2/BPIO at T > ~120 K-the Verwey transition temperature of Fe3O4 (TV). However, an enhanced magnetization is achieved at T < TV. In the latter case, a comparative analysis of the transport properties of Pt/WS2/BPIO and Pt/BPIO from AHE measurements reveals ferromagnetic coupling at the WS2/BPIO interface. Our study forms the foundation for understanding MPE-mediated interfacial properties and paves a new pathway for designing 2D TMD/magnet heterostructures for applications in spintronics, opto-spincaloritronics, and valleytronics.
Collapse
Affiliation(s)
- Chang-Ming Hung
- Department of Physics, University of South Florida, Tampa, FL 33620, USA
| | - Diem Thi-Xuan Dang
- Department of Physics, University of South Florida, Tampa, FL 33620, USA
| | - Amit Chanda
- Department of Physics, University of South Florida, Tampa, FL 33620, USA
| | - Derick Detellem
- Department of Physics, University of South Florida, Tampa, FL 33620, USA
| | - Noha Alzahrani
- Department of Physics, University of South Florida, Tampa, FL 33620, USA
| | - Nalaka Kapuruge
- Department of Physics, University of South Florida, Tampa, FL 33620, USA
| | - Yen T. H. Pham
- Department of Physics, University of South Florida, Tampa, FL 33620, USA
| | - Mingzu Liu
- Department of Physics, The Pennsylvania State University, University Park, PA 16802, USA
| | - Da Zhou
- Department of Physics, The Pennsylvania State University, University Park, PA 16802, USA
| | | | - Darío A. Arena
- Department of Physics, University of South Florida, Tampa, FL 33620, USA
| | - Mauricio Terrones
- Department of Physics, The Pennsylvania State University, University Park, PA 16802, USA
| | - Sarath Witanachchi
- Department of Physics, University of South Florida, Tampa, FL 33620, USA
| | - Lilia M. Woods
- Department of Physics, University of South Florida, Tampa, FL 33620, USA
- Correspondence: (L.M.W.); (M.-H.P.)
| | - Hariharan Srikanth
- Department of Physics, University of South Florida, Tampa, FL 33620, USA
| | - Manh-Huong Phan
- Department of Physics, University of South Florida, Tampa, FL 33620, USA
- Correspondence: (L.M.W.); (M.-H.P.)
| |
Collapse
|
7
|
Cai L, Yu C, Zhao W, Li Y, Feng H, Zhou HA, Wang L, Zhang X, Zhang Y, Shi Y, Zhang J, Yang L, Jiang W. The Giant Spin-to-Charge Conversion of the Layered Rashba Material BiTeI. Nano Lett 2022; 22:7441-7448. [PMID: 36099337 DOI: 10.1021/acs.nanolett.2c02354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Rashba spin-orbit coupling (SOC) could facilitate an efficient interconversion between spin and charge currents. Among various systems, BiTeI holds one of the largest Rashba-type spin splittings. Unlike other Rashba systems (e.g., Bi/Ag and Bi2Se3), an experimental investigation of the spin-to-charge interconversion in BiTeI remains to be explored. Through performing an angle-resolved photoemission spectroscopy (ARPES) measurement, such a large Rashba-type spin splitting with a Rashba parameter αR = 3.68 eV Å is directly identified. By studying the spin pumping effect in the BiTeI/NiFe bilayer, we reveal a very large inverse Rashba-Edelstein length λIREE ≈ 1.92 nm of BiTeI at room temperature. Furthermore, the λIREE monotonously increases to 5.00 nm at 60 K, indicating an enhanced Rashba SOC at low temperature. These results suggest that BiTeI films with the giant Rashba SOC are promising for achieving efficient spin-to-charge interconversion, which could be implemented for building low-power-consumption spin-orbitronic devices.
Collapse
Affiliation(s)
- Li Cai
- State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Tsinghua University, Beijing 100084, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100084, China
| | - Chenglin Yu
- State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Tsinghua University, Beijing 100084, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100084, China
| | - Wenxuan Zhao
- State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Tsinghua University, Beijing 100084, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100084, China
| | - Yong Li
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Hongmei Feng
- State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Tsinghua University, Beijing 100084, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100084, China
| | - Heng-An Zhou
- State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Tsinghua University, Beijing 100084, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100084, China
| | - Ledong Wang
- State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Tsinghua University, Beijing 100084, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100084, China
| | - Xiaofang Zhang
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| | - Ying Zhang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| | - Youguo Shi
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Jinsong Zhang
- State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Tsinghua University, Beijing 100084, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100084, China
| | - Lexian Yang
- State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Tsinghua University, Beijing 100084, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100084, China
| | - Wanjun Jiang
- State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Tsinghua University, Beijing 100084, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100084, China
| |
Collapse
|
8
|
Bangar H, Kumar A, Chowdhury N, Mudgal R, Gupta P, Yadav RS, Das S, Muduli PK. Large Spin-To-Charge Conversion at the Two-Dimensional Interface of Transition-Metal Dichalcogenides and Permalloy. ACS Appl Mater Interfaces 2022; 14:41598-41604. [PMID: 36052925 DOI: 10.1021/acsami.2c11162] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Spin-to-charge conversion is an essential requirement for the implementation of spintronic devices. Recently, monolayers (MLs) of semiconducting transition-metal dichalcogenides (TMDs) have attracted considerable interest for spin-to-charge conversion due to their high spin-orbit coupling and lack of inversion symmetry in their crystal structure. However, reports of direct measurement of spin-to-charge conversion at TMD-based interfaces are very much limited. Here, we report on the room-temperature observation of a large spin-to-charge conversion arising from the interface of Ni80Fe20 (Py) and four distinct large-area (∼5 × 2 mm2) ML TMDs, namely, MoS2, MoSe2, WS2, and WSe2. We show that both spin mixing conductance and the Rashba efficiency parameter (λIREE) scale with the spin-orbit coupling strength of the ML TMD layers. The λIREE parameter is found to range between -0.54 and -0.76 nm for the four ML TMDs, demonstrating a large spin-to-charge conversion. Our findings reveal that the TMD/ferromagnet interface can be used for efficient generation and detection of spin current, opening new opportunities for novel spintronic devices.
Collapse
Affiliation(s)
- Himanshu Bangar
- Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Akash Kumar
- Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
- Department of Physics, University of Gothenburg, Gothenburg 412 96, Sweden
| | - Niru Chowdhury
- Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Richa Mudgal
- Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Pankhuri Gupta
- Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Ram Singh Yadav
- Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Samaresh Das
- Center for Applied Research in Electronics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Pranaba Kishor Muduli
- Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| |
Collapse
|
9
|
Liu T, Shen L, Cheng SD, Wang H, Li Y, Liu M. Interfacial Modulation on Co 0.2Fe 2.8O 4 Epitaxial Thin Films for Anomalous Hall Sensor Applications. ACS Appl Mater Interfaces 2022; 14:37887-37893. [PMID: 35950982 DOI: 10.1021/acsami.2c07575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Magnetic oxide films with a strong anomalous Hall effect (AHE) have attracted much attention due to their strong sensitivity and high polarization for magnetic sensor applications. However, the linearity of the anomalous Hall sensors still needs improving. In this work, we propose to use the interface regulation to improve the linearity of the AHE. We grow spinel ferrite Co0.2Fe2.8O4 (CoFeO) thin films on MgAl2O4 (MAO) substrates and alter their interfacial properties by inserting a graphene layer between the MAO substrate and the CoFeO film. Through a detailed structure and performance analysis, it reveals that the insertion of graphene has not broken the epitaxial nature of the films but endows the film with a nanopillar-like structure. A series of electrical tests show that the Hall resistance signal of our thin film system has high sensitivity and high linearity to the magnetic field. Reduced hysteresis and better linearity of the anomalous Hall resistance were found in the graphene-inserted heterostructure due to differences in the nanostructure and possibly interfacial coupling. These results suggest that interfacial engineering offers a pathway to tune the performance of ferrite thin film systems for sensor applications.
Collapse
Affiliation(s)
- Tianyu Liu
- School of Microelectronics, Xi'an Jiaotong University, Xi'an 710049, China
| | - Lvkang Shen
- School of Microelectronics, Xi'an Jiaotong University, Xi'an 710049, China
| | - Shao-Dong Cheng
- School of Microelectronics, Xi'an Jiaotong University, Xi'an 710049, China
| | - He Wang
- School of Microelectronics, Xi'an Jiaotong University, Xi'an 710049, China
| | - Yixuan Li
- School of Microelectronics, Xi'an Jiaotong University, Xi'an 710049, China
| | - Ming Liu
- School of Microelectronics, Xi'an Jiaotong University, Xi'an 710049, China
| |
Collapse
|
10
|
Zollner K, Fabian J. Engineering Proximity Exchange by Twisting: Reversal of Ferromagnetic and Emergence of Antiferromagnetic Dirac Bands in Graphene/Cr_{2}Ge_{2}Te_{6}. Phys Rev Lett 2022; 128:106401. [PMID: 35333087 DOI: 10.1103/physrevlett.128.106401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 12/22/2021] [Accepted: 02/17/2022] [Indexed: 06/14/2023]
Abstract
We investigate the twist-angle and gate dependence of the proximity exchange coupling in twisted graphene on monolayer Cr_{2}Ge_{2}Te_{6} from first principles. The proximitized Dirac band dispersions of graphene are fitted to a model Hamiltonian, yielding effective sublattice-resolved proximity-induced exchange parameters (λ_{ex}^{A} and λ_{ex}^{B}) for a series of twist angles between 0° and 30°. For aligned layers (0° twist angle), the exchange coupling of graphene is the same on both sublattices, λ_{ex}^{A}≈λ_{ex}^{B}≈4 meV, while the coupling is reversed at 30° (with λ_{ex}^{A}≈λ_{ex}^{B}≈-4 meV). Remarkably, at 19.1° the induced exchange coupling becomes antiferromagnetic: λ_{ex}^{A}<0, λ_{ex}^{B}>0. Further tuning is provided by a transverse electric field and the interlayer distance. The predicted proximity magnetization reversal and emergence of an antiferromagnetic Dirac dispersion make twisted graphene/Cr_{2}Ge_{2}Te_{6} bilayers a versatile platform for realizing topological phases and for spintronics applications.
Collapse
Affiliation(s)
- Klaus Zollner
- Institute for Theoretical Physics, University of Regensburg, 93040 Regensburg, Germany
| | - Jaroslav Fabian
- Institute for Theoretical Physics, University of Regensburg, 93040 Regensburg, Germany
| |
Collapse
|
11
|
Yu S, Tang J, Wang Y, Xu F, Li X, Wang X. Recent advances in two-dimensional ferromagnetism: strain-, doping-, structural- and electric field-engineering toward spintronic applications. Sci Technol Adv Mater 2022; 23:140-160. [PMID: 35185390 PMCID: PMC8856075 DOI: 10.1080/14686996.2022.2030652] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 01/03/2022] [Accepted: 01/09/2022] [Indexed: 05/27/2023]
Abstract
Since the first report on truly two-dimensional (2D) magnetic materials in 2017, a wide variety of merging 2D magnetic materials with unusual physical characteristics have been discovered and thus provide an effective platform for exploring the associated novel 2D spintronic devices, which have been made significant progress in both theoretical and experimental studies. Herein, we make a comprehensive review on the recent scientific endeavors and advances on the various engineering strategies on 2D ferromagnets, such as strain-, doping-, structural- and electric field-engineering, toward practical spintronic applications, including spin tunneling junctions, spin field-effect transistors and spin logic gate, etc. In the last, we discuss on current challenges and future opportunities in this field, which may provide useful guidelines for scientists who are exploring the fundamental physical properties and practical spintronic devices of low-dimensional magnets.
Collapse
Affiliation(s)
- Sheng Yu
- Institute of Information Technology, Shenzhen Institute of Information Technology, Shenzhen, China
- Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Junyu Tang
- Department of Physics and Astronomy, University of California, Riverside, CA, USA
| | - Yu Wang
- Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Feixiang Xu
- Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Xiaoguang Li
- Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Xinzhong Wang
- Institute of Information Technology, Shenzhen Institute of Information Technology, Shenzhen, China
| |
Collapse
|
12
|
Lee WY, Park NW, Kang MS, Kim GS, Yoon YG, Lee S, Choi KY, Kim KS, Kim JH, Seong MJ, Kikkawa T, Saitoh E, Lee SK. Extrinsic Surface Magnetic Anisotropy Contribution in Pt/Y 3Fe 5O 12 Interface in Longitudinal Spin Seebeck Effect by Graphene Interlayer. ACS Appl Mater Interfaces 2021; 13:45097-45104. [PMID: 34496563 DOI: 10.1021/acsami.1c13180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
A recent study found that magnetization curves for Y3Fe5O12 (YIG) slab and thick films (>20 μm thick) differed from bulk system curves by their longitudinal spin Seebeck effect in a Pt/YIG bilayer system. The deviation was due to intrinsic YIG surface magnetic anisotropy, which is difficult to adopt extrinsic surface magnetic anisotropy even when in contact with other materials on the YIG surface. This study experimentally demonstrates evidence for extrinsic YIG surface magnetic anisotropy when in contact with a diamagnetic graphene interlayer by observing the spin Seebeck effect, directly proving intrinsic YIG surface magnetic anisotropy interruption. We show the Pt/YIG bilayer system graphene interlayer role using large area single and multilayered graphenes using the longitudinal spin Seebeck effect at room temperature, and address the presence of surface magnetic anisotropy due to magnetic proximity between graphene and YIG layer. These findings suggest a promising route to understand new physics of spin Seebeck effect in spin transport.
Collapse
Affiliation(s)
- Won-Yong Lee
- Department of Physics, Chung-Ang University, Seoul 06974, Republic of Korea
| | - No-Won Park
- Department of Physics, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Min-Sung Kang
- Department of Physics, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Gil-Sung Kim
- Department of Physics, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Young-Gui Yoon
- Department of Physics, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Suheon Lee
- Deopartment of Physics, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Kwang-Yong Choi
- Deopartment of Physics, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Keun Soo Kim
- Department of Physics and Astronomy, Sejong University, Seoul 05006, Republic of Korea
| | - Jin-Hyuk Kim
- Department of Physics, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Maeng-Je Seong
- Department of Physics, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Takashi Kikkawa
- Department of Applied Physics, The University of Tokyo, Tokyo 113-8656, Japan
| | - Eiji Saitoh
- Department of Applied Physics, The University of Tokyo, Tokyo 113-8656, Japan
- WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
- Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
| | - Sang-Kwon Lee
- Department of Physics, Chung-Ang University, Seoul 06974, Republic of Korea
- WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
| |
Collapse
|
13
|
Holanda J, Santos OA, Mendes JBS, Rezende SM. Spin-to-charge conversion and interface-induced spin Hall magnetoresistance in yttrium iron garnet/metallic bilayers. J Phys Condens Matter 2021; 33:435803. [PMID: 34293724 DOI: 10.1088/1361-648x/ac16f7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 07/22/2021] [Indexed: 06/13/2023]
Abstract
We report the investigation of spin-to-charge current interconversion process in hybrid structures of yttrium iron garnet (YIG)/metallic bilayers by means of two different experimental techniques: spin pumping effect (SPE) and spin Hall magnetoresistance (SMR). We demonstrate the evidence of a correlation between spin-to-charge conversion and SMR in bilayers of YIG/Pd, YIG/Pt, and YIG/IrMn. The correlation was verified directly in the spin Hall angles and the amplitudes of the voltage signals measured by the SPE and SMR techniques. The detection of SMR was carried out using the modulated magnetoresistance technique and lock-in amplifier detection. For these measurements, we present a simple model for the interpretation of the results. The results allow us to conclude that indeed the interface in the YIG/metallic bilayers has a dominant role in the spin-to-charge current conversion and SMR.
Collapse
Affiliation(s)
- J Holanda
- Departamento de Física, Universidade Federal do Espírito Santo, 29075-910, Vitória, ES, Brazil
| | - O Alves Santos
- Physics of Nanodevices, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, Groningen, AG 9747, The Netherlands
| | - J B S Mendes
- Departamento de Física, Universidade Federal de Viçosa, 36570-900 Viçosa, MG, Brazil
| | - S M Rezende
- Departamento de Física, Universidade Federal de Pernambuco, 50670-901, Recife, PE, Brazil
| |
Collapse
|
14
|
Ghiasi TS, Kaverzin AA, Dismukes AH, de Wal DK, Roy X, van Wees BJ. Electrical and thermal generation of spin currents by magnetic bilayer graphene. Nat Nanotechnol 2021; 16:788-794. [PMID: 33958763 DOI: 10.1038/s41565-021-00887-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 03/02/2021] [Indexed: 05/28/2023]
Abstract
Ultracompact spintronic devices greatly benefit from the implementation of two-dimensional materials that provide large spin polarization of charge current together with long-distance transfer of spin information. Here spin-transport measurements in bilayer graphene evidence a strong spin-charge coupling due to a large induced exchange interaction by the proximity of an interlayer antiferromagnet (CrSBr). This results in the direct detection of the spin polarization of conductivity (up to 14%) and a spin-dependent Seebeck effect in the magnetic graphene. The efficient electrical and thermal spin-current generation is the most technologically relevant aspect of magnetism in graphene, controlled here by the antiferromagnetic dynamics of CrSBr. The high sensitivity of spin transport in graphene to the magnetization of the outermost layer of the adjacent antiferromagnet, furthermore, enables the read-out of a single magnetic sublattice. The combination of gate-tunable spin-dependent conductivity and Seebeck coefficient with long-distance spin transport in a single two-dimensional material promises ultrathin magnetic memory and sensory devices based on magnetic graphene.
Collapse
Affiliation(s)
- Talieh S Ghiasi
- Zernike Institute for Advanced Materials, University of Groningen, Groningen, the Netherlands.
| | - Alexey A Kaverzin
- Zernike Institute for Advanced Materials, University of Groningen, Groningen, the Netherlands
| | | | - Dennis K de Wal
- Zernike Institute for Advanced Materials, University of Groningen, Groningen, the Netherlands
| | - Xavier Roy
- Department of Chemistry, Columbia University, New York, NY, USA
| | - Bart J van Wees
- Zernike Institute for Advanced Materials, University of Groningen, Groningen, the Netherlands
| |
Collapse
|
15
|
Xie Y, Zhao J, Hu Y, Ye X, Xie Y, Cao R. Outstanding spin-transport properties of a flexible phosphorene photodetector driven by the photogalvanic effect under mechanical strains. Phys Chem Chem Phys 2021; 23:11961-11967. [PMID: 34002190 DOI: 10.1039/d0cp06712a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Monolayer phosphorene has outstanding spintronic properties including a nanosecond spin lifetime, and micrometer spin relaxation length, combined with excellent mechanical flexibility, making it rather attractive in low-dimensional flexible spintronic devices. However, knowledge on the spin-transport properties of phosphorene under mechanical strain is currently very limited. Here, we study the transport properties of the spin-polarized photocurrent in the flexible Ni-phosphorene-Ni photodetector, which is driven by the photogalvanic effect (PGE) under mechanical tension stress and bending. Broadband PGE photocurrent is generated at zero bias under the illumination of linearly polarized light due to the broken inversion symmetry of the photodetector. Remarkable spin-transport performances including the fully spin-polarized photocurrent, perfect spin-valve effect, and enhanced pure spin current are generated in a broad visible range by applying appropriate mechanical tension stress or bending. Our results indicate that the PGE-driven phosphorene-based photodetector has promising applications in flexible and low-power spintronic devices.
Collapse
Affiliation(s)
- Yufeng Xie
- State Key Laboratory of ASIC and systems, School of Microelectronics, Fudan University, Shanghai 200433, China
| | | | | | | | | | | |
Collapse
|
16
|
Abstract
Spintronics is the most promising technology to develop alternative multi-functional, high-speed, low-energy electronic devices. Due to their unusual physical characteristics, emerging two-dimensional (2D) materials provide a new platform for exploring novel spintronic devices. Recently, 2D spintronics has made great progress in both theoretical and experimental researches. Here, the progress of 2D spintronics has been reviewed. In the last, the current challenges and future opportunities have been pointed out in this field.
Collapse
Affiliation(s)
- Guojing Hu
- Department of Materials Science and Engineering, CAS Key Lab of Materials for Energy Conversion, Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, 230026 Anhui China
- Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei, 230026 China
| | - Bin Xiang
- Department of Materials Science and Engineering, CAS Key Lab of Materials for Energy Conversion, Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, 230026 Anhui China
- Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei, 230026 China
| |
Collapse
|
17
|
Yu T, Bauer GEW. Noncontact Spin Pumping by Microwave Evanescent Fields. Phys Rev Lett 2020; 124:236801. [PMID: 32603158 DOI: 10.1103/physrevlett.124.236801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 04/13/2020] [Accepted: 05/20/2020] [Indexed: 06/11/2023]
Abstract
The angular momentum of evanescent light fields has been studied in nano-optics and plasmonics but not in the microwave regime. Here we predict noncontact pumping of electron spin currents in conductors by the evanescent stray fields of excited magnetic nanostructures. The coherent transfer of the photon to the electron spin is proportional to the g factor, which is large in narrow gap semiconductors and surface states of topological insulators. The spin pumping current is chiral when the spin susceptibility displays singularities that indicate collective states. However, 1D systems with linear dispersion at the Fermi energy, such as metallic carbon nanotubes, are an exception since spin pumping is chiral even without interactions.
Collapse
Affiliation(s)
- Tao Yu
- Kavli Institute of NanoScience, Delft University of Technology, 2628 CJ Delft, Netherlands
| | - Gerrit E W Bauer
- Kavli Institute of NanoScience, Delft University of Technology, 2628 CJ Delft, Netherlands
- Institute for Materials Research and WPI-AIMR and CSRN, Tohoku University, Sendai 980-8577, Japan
| |
Collapse
|
18
|
Högl P, Frank T, Zollner K, Kochan D, Gmitra M, Fabian J. Quantum Anomalous Hall Effects in Graphene from Proximity-Induced Uniform and Staggered Spin-Orbit and Exchange Coupling. Phys Rev Lett 2020; 124:136403. [PMID: 32302179 DOI: 10.1103/physrevlett.124.136403] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 12/27/2019] [Accepted: 01/27/2020] [Indexed: 06/11/2023]
Abstract
We investigate an effective model of proximity modified graphene (or symmetrylike materials) with broken time-reversal symmetry. We predict the appearance of quantum anomalous Hall phases by computing bulk band gap and Chern numbers for benchmark combinations of system parameters. Allowing for staggered exchange field enables quantum anomalous Hall effect in flat graphene with Chern number C=1. We explicitly show edge states in zigzag and armchair nanoribbons and explore their localization behavior. Remarkably, the combination of staggered intrinsic spin-orbit and uniform exchange coupling gives topologically protected (unlike in time-reversal systems) pseudohelical states, whose spin is opposite in opposite zigzag edges. Rotating the magnetization from out of plane to in plane makes the system trivial, allowing us to control topological phase transitions. We also propose, using density functional theory, a material platform-graphene on Ising antiferromagnet MnPSe_{3}-to realize staggered exchange (pseudospin Zeeman) coupling.
Collapse
Affiliation(s)
- Petra Högl
- Institute for Theoretical Physics, University of Regensburg, 93040 Regensburg, Germany
| | - Tobias Frank
- Institute for Theoretical Physics, University of Regensburg, 93040 Regensburg, Germany
| | - Klaus Zollner
- Institute for Theoretical Physics, University of Regensburg, 93040 Regensburg, Germany
| | - Denis Kochan
- Institute for Theoretical Physics, University of Regensburg, 93040 Regensburg, Germany
| | - Martin Gmitra
- Department of Theoretical Physics and Astrophysics, Pavol Jozef Šafárik University, 04001 Košice, Slovakia
| | - Jaroslav Fabian
- Institute for Theoretical Physics, University of Regensburg, 93040 Regensburg, Germany
| |
Collapse
|
19
|
Tang C, Zhang Z, Lai S, Tan Q, Gao WB. Magnetic Proximity Effect in Graphene/CrBr 3 van der Waals Heterostructures. Adv Mater 2020; 32:e1908498. [PMID: 32130750 DOI: 10.1002/adma.201908498] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2019] [Revised: 02/17/2020] [Indexed: 05/22/2023]
Abstract
2D van der Waals heterostructures serve as a promising platform to exploit various physical phenomena in a diverse range of novel spintronic device applications. Efficient spin injection is the prerequisite for these devices. The recent discovery of magnetic 2D materials leads to the possibility of fully 2D van der Waals spintronics devices by implementing spin injection through the magnetic proximity effect (MPE). Here, the investigation of MPE in 2D graphene/CrBr3 van der Waals heterostructures is reported, which is probed by the Zeeman spin Hall effect through non-local measurements. Quantitative estimation of the Zeeman splitting field demonstrates a significant MPE field even in a low magnetic field. Furthermore, the observed anomalous longitudinal resistance changes at the Dirac point RXX,D with increasing magnetic field near ν = 0 may be attributed to the MPE-induced new ground state phases. This MPE revealed in the graphene/CrBr3 van der Waals heterostructures therefore provides a solid physics basis and key functionality for next-generation 2D spin logic and memory devices.
Collapse
Affiliation(s)
- Chaolong Tang
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
| | - Zhaowei Zhang
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
| | - Shen Lai
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
| | - Qinghai Tan
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
| | - Wei-Bo Gao
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
- The Photonics Institute and Centre for Disruptive Photonic Technologies, Nanyang Technological University, Singapore, 637371, Singapore
| |
Collapse
|
20
|
Benítez LA, Savero Torres W, Sierra JF, Timmermans M, Garcia JH, Roche S, Costache MV, Valenzuela SO. Tunable room-temperature spin galvanic and spin Hall effects in van der Waals heterostructures. Nat Mater 2020; 19:170-175. [PMID: 31907417 DOI: 10.1038/s41563-019-0575-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 11/28/2019] [Indexed: 06/10/2023]
Abstract
Spin-orbit coupling stands as a powerful tool to interconvert charge and spin currents and to manipulate the magnetization of magnetic materials through spin-torque phenomena. However, despite the diversity of existing bulk materials and the recent advent of interfacial and low-dimensional effects, control of this interconversion at room temperature remains elusive. Here, we demonstrate strongly enhanced room-temperature spin-to-charge interconversion in graphene driven by the proximity of WS2. By performing spin precession experiments in appropriately designed Hall bars, we separate the contributions of the spin Hall and the spin galvanic effects. Remarkably, their corresponding conversion efficiencies can be tailored by electrostatic gating in magnitude and sign, peaking near the charge neutrality point with an equivalent magnitude that is comparable to the largest efficiencies reported to date. Such electric-field tunability provides a building block for spin generation free from magnetic materials and for ultra-compact magnetic memory technologies.
Collapse
Affiliation(s)
- L Antonio Benítez
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, Spain.
- Universitat Autònoma de Barcelona, Bellaterra, Spain.
| | - Williams Savero Torres
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, Spain.
| | - Juan F Sierra
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, Spain
| | - Matias Timmermans
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, Spain
- Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Jose H Garcia
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, Spain
| | - Stephan Roche
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Marius V Costache
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, Spain
| | - Sergio O Valenzuela
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, Spain.
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain.
| |
Collapse
|
21
|
Ghadiyali M, Chacko S. Hydrogenated-Graphene-Encapsulated Graphene: A Versatile Material for Device Applications. ACS Omega 2019; 4:17494-17503. [PMID: 31656921 PMCID: PMC6812122 DOI: 10.1021/acsomega.9b02329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 08/16/2019] [Indexed: 06/10/2023]
Abstract
Graphene and its heterostructures exhibit interesting electronic properties and are explored for quantum spin Hall effect (QSHE) and magnetism-based device applications. In present work, we propose a heterostructure of graphene encapsulated by hydrogenated-graphene, which could be a promising candidate for a variety of device applications. We have carried out DFT calculations on this system to check its feasibility to be a versatile material. We found that electronic states of multilayer pristine graphene, especially the Dirac cone, an important feature to host QSHE, can be preserved by sandwiching it by fully hydrogenated graphene. The interference of electronic states of hydrogenated graphene was insignificant with those of graphene. States of graphene were also found to be stable upon application of an electric field up to ±2.5 V/nm. For device applications, multilayer graphene or its heterostructures are required to be deposited on a substrate, which interacts with the system opening up a gap at the Dirac cone making it less suitable for QSHE applications, and hydrogenated graphene can prevent it. Magnetization in these hydrogenated-graphene-sandwiched graphene systems may be induced by creating vacancies or distortions in hydrogenated graphene, which was found to have a minimal effect on graphene's electronic states, thus providing an additional degree of manipulation. We also performed a set of calculations to explore its applicability for detecting some molecules. Our results on trilayer graphene encapsulated by hydrogenated graphene indicate that all these observations can be generalized for systems with a larger number of graphene layers, indicating that multilayer graphene sandwiched between two hydrogenated graphene is a versatile material that can be used in QSHE and sensor devices.
Collapse
|
22
|
Dc M, Chen JY, Peterson T, Sahu P, Ma B, Mousavi N, Harjani R, Wang JP. Observation of High Spin-to-Charge Conversion by Sputtered Bismuth Selenide Thin Films at Room Temperature. Nano Lett 2019; 19:4836-4844. [PMID: 31283247 DOI: 10.1021/acs.nanolett.8b05011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We investigated spin-to-charge conversion in sputtered Bi43Se57/Co20Fe60B20 heterostructures with in-plane magnetization at room temperature. High spin-to-charge conversion voltage signals have been observed at room temperature. The transmission electron microscope images show that the sputtered bismuth selenide thin films are nanogranular in structure. The spin-pumping voltage decreases with an increase in the size of the grains. The inverse Edelstein effect length (λIEE) is estimated to be as large as 0.32 nm. The large λIEE is due to the spin-momentum locking and is further enhanced by quantum confinement in the nanosized grains of the sputtered bismuth selenide films. We also investigated the effect on spin-pumping voltage due to the insertion of layers of MgO and Ag. The MgO insertion layer has almost completely suppressed the spin-pumping voltage, whereas the Ag insertion layer has enhanced the λIEE by 43%.
Collapse
Affiliation(s)
- Mahendra Dc
- School of Physics and Astronomy , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Jun-Yang Chen
- Department of Electrical and Computer Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Thomas Peterson
- School of Physics and Astronomy , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Protuysh Sahu
- School of Physics and Astronomy , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Bin Ma
- Department of Electrical and Computer Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Naser Mousavi
- Department of Electrical and Computer Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Ramesh Harjani
- Department of Electrical and Computer Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Jian-Ping Wang
- School of Physics and Astronomy , University of Minnesota , Minneapolis , Minnesota 55455 , United States
- Department of Electrical and Computer Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| |
Collapse
|
23
|
Abstract
Magnetism, originating from the moving charges and spin of elementary particles, has revolutionized important technologies such as data storage and biomedical imaging, and continues to bring forth new phenomena in emergent materials and reduced dimensions. The recently discovered two-dimensional (2D) magnetic van der Waals crystals provide ideal platforms for understanding 2D magnetism, the control of which has been fueling opportunities for atomically thin, flexible magneto-optic and magnetoelectric devices (such as magnetoresistive memories and spin field-effect transistors). The seamless integration of 2D magnets with dissimilar electronic and photonic materials opens up exciting possibilities for unprecedented properties and functionalities. We review the progress in this area and identify the possible directions for device applications, which may lead to advances in spintronics, sensors, and computing.
Collapse
|
24
|
Tan Q, Wang Q, Liu Y, Liu C, Feng X, Yu D. Enhanced magnetic properties and tunable Dirac point of graphene/Mn-doped monolayer MoS 2 heterostructures. J Phys Condens Matter 2018; 30:305304. [PMID: 29900880 DOI: 10.1088/1361-648x/aacca2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Graphene is one of the most promising spintronic materials due to its high carrier mobility. However, the absence of a band gap and ferromagnetic order in graphene seriously limit its applications in spintronics. How to utilize its high carrier mobility as well as mediate its electronic structure remains a challenge. Herein, we design a novel composite, which is composed of graphene and Mn-doped monolayer MoS2. The magnetic properties and electronic structures of graphene/Mn-doped monolayer MoS2 heterostructures were studied by using density functional theory (DFT) with the van der Waals (vdW) correlations (DFT-D). We found that the heterostructures show increased magnetic moments and more stable ferromagnetic (FM) states compared with that of isolated Mn-doped MoS2 monolayer. Our further studies show that many electrons are transferred to Mn-doped MoS2 monolayer from graphene, which causes the Fermi level to shift down below the Dirac cone about 0.59 eV. The transfered electrons also enhance the FM coupling between Mn ions. Graphene is partially spin polarized because of the magnetic proximity effect, which leads to the spin-dependent gaps for spin-up (16.1 meV) and spin-down (5 meV) at Dirac point, respectively. The introduction of sulfur (S) vacancy to the interface results in a much more stable FM structure and a higher total magnetic moment of the FM state; furthermore, it raises the spin polarization of graphene π orbitals and opens up a small band gap of about 7 meV. These findings propose a new route to facilitate the design of spintronic devices which both need stable ferromagnetism and finite band gap.
Collapse
Affiliation(s)
- Qiuhong Tan
- College of Physics and Electronic Information, Yunnan Normal University, Yunnan Kunming 650500, People's Republic of China. Yunnan Provincial Key Laboratory for Photoelectric Information Technology, Yunnan Normal University, Yunnan Kunming 650500, People's Republic of China
| | | | | | | | | | | |
Collapse
|
25
|
Kuschel O, Pathé N, Schemme T, Ruwisch K, Rodewald J, Buss R, Bertram F, Kuschel T, Kuepper K, Wollschläger J. Impact of Strain and Morphology on Magnetic Properties of Fe₃O₄/NiO Bilayers Grown on Nb:SrTiO₃(001) and MgO(001). Materials (Basel) 2018; 11:E1122. [PMID: 29966373 DOI: 10.3390/ma11071122] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 06/26/2018] [Accepted: 06/27/2018] [Indexed: 11/17/2022]
Abstract
We present a comparative study of the morphology and structural as well as magnetic properties of crystalline Fe₃O₄/NiO bilayers grown on both MgO(001) and SrTiO₃(001) substrates by reactive molecular beam epitaxy. These structures were investigated by means of X-ray photoelectron spectroscopy, low-energy electron diffraction, X-ray reflectivity and diffraction, as well as vibrating sample magnetometry. While the lattice mismatch of NiO grown on MgO(001) was only 0.8%, it was exposed to a lateral lattice mismatch of −6.9% if grown on SrTiO₃. In the case of Fe₃O₄, the misfit strain on MgO(001) and SrTiO₃(001) amounted to 0.3% and −7.5%, respectively. To clarify the relaxation process of the bilayer system, the film thicknesses of the magnetite and nickel oxide films were varied between 5 and 20 nm. While NiO films were well ordered on both substrates, Fe₃O₄ films grown on NiO/SrTiO₃ exhibited a higher surface roughness as well as lower structural ordering compared to films grown on NiO/MgO. Further, NiO films grew pseudomorphic in the investigated thickness range on MgO substrates without any indication of relaxation, whereas on SrTiO₃ the NiO films showed strong strain relaxation. Fe₃O₄ films also exhibited strong relaxation, even for films of 5 nm thickness on both NiO/MgO and NiO/SrTiO₃. The magnetite layers on both substrates showed a fourfold magnetic in-plane anisotropy with magnetic easy axes pointing in 100 directions. The coercive field was strongly enhanced for magnetite grown on NiO/SrTiO₃ due to the higher density of structural defects, compared to magnetite grown on NiO/MgO.
Collapse
|
26
|
Averyanov DV, Sokolov IS, Tokmachev AM, Parfenov OE, Karateev IA, Taldenkov AN, Storchak VG. High-Temperature Magnetism in Graphene Induced by Proximity to EuO. ACS Appl Mater Interfaces 2018; 10:20767-20774. [PMID: 29806934 DOI: 10.1021/acsami.8b04289] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Addition of magnetism to spectacular properties of graphene may lead to novel topological states and design of spin logic devices enjoying low power consumption. A significant progress is made in defect-induced magnetism in graphene-selective elimination of p z orbitals (by vacancies or adatoms) at triangular sublattices tailors graphene magnetism. Proximity to a magnetic insulator is a less invasive way, which is being actively explored now. Integration of graphene with the ferromagnetic semiconductor EuO has much to offer, especially in terms of proximity-induced spin-orbit interactions. Here, we synthesize films of EuO on graphene using reactive molecular beam epitaxy. Their quality is attested by electron and X-ray diffraction, cross-sectional electron microscopy, and Raman and magnetization measurements. Studies of electron transport reveal a magnetic transition at TC* ≈ 220 K, well above the Curie temperature 69 K of EuO. Up to TC*, the dependence R xy( B) is strongly nonlinear, suggesting the presence of the anomalous Hall effect. The role of synthesis conditions is highlighted by studies of an overdoped structure. The results justify the use of the EuO/graphene system in spintronics.
Collapse
Affiliation(s)
- Dmitry V Averyanov
- National Research Center "Kurchatov Institute" , Kurchatov Sq. 1 , Moscow 123182 , Russia
| | - Ivan S Sokolov
- National Research Center "Kurchatov Institute" , Kurchatov Sq. 1 , Moscow 123182 , Russia
| | - Andrey M Tokmachev
- National Research Center "Kurchatov Institute" , Kurchatov Sq. 1 , Moscow 123182 , Russia
| | - Oleg E Parfenov
- National Research Center "Kurchatov Institute" , Kurchatov Sq. 1 , Moscow 123182 , Russia
| | - Igor A Karateev
- National Research Center "Kurchatov Institute" , Kurchatov Sq. 1 , Moscow 123182 , Russia
| | - Alexander N Taldenkov
- National Research Center "Kurchatov Institute" , Kurchatov Sq. 1 , Moscow 123182 , Russia
| | - Vyacheslav G Storchak
- National Research Center "Kurchatov Institute" , Kurchatov Sq. 1 , Moscow 123182 , Russia
| |
Collapse
|
27
|
Abstract
This review discusses the electronic properties and the prospective research directions of superconductor-graphene heterostructures. The basic electronic properties of graphene are introduced to highlight the unique possibility of combining two seemingly unrelated physics, superconductivity and relativity. We then focus on graphene-based Josephson junctions, one of the most versatile superconducting quantum devices. The various theoretical methods that have been developed to describe graphene Josephson junctions are examined, together with their advantages and limitations, followed by a discussion on the advances in device fabrication and the relevant length scales. The phase-sensitive properties and phase-particle dynamics of graphene Josephson junctions are examined to provide an understanding of the underlying mechanisms of Josephson coupling via graphene. Thereafter, microscopic transport of correlated quasiparticles produced by Andreev reflections at superconducting interfaces and their phase-coherent behaviors are discussed. Quantum phase transitions studied with graphene as an electrostatically tunable 2D platform are reviewed. The interplay between proximity-induced superconductivity and the quantum-Hall phase is discussed as a possible route to study topological superconductivity and non-Abelian physics. Finally, a brief summary on the prospective future research directions is given.
Collapse
Affiliation(s)
- Gil-Ho Lee
- Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea. Department of Physics, Harvard University, Cambridge, MA 02138, United States of America
| | | |
Collapse
|
28
|
Peng B, Li Q, Liang X, Song P, Li J, He K, Fu D, Li Y, Shen C, Wang H, Wang C, Liu T, Zhang L, Lu H, Wang X, Zhao J, Xie J, Wu M, Bi L, Deng L, Loh KP. Valley Polarization of Trions and Magnetoresistance in Heterostructures of MoS 2 and Yttrium Iron Garnet. ACS Nano 2017; 11:12257-12265. [PMID: 29182851 DOI: 10.1021/acsnano.7b05743] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Manipulation of spin degree of freedom (DOF) of electrons is the fundamental aspect of spintronic and valleytronic devices. Two-dimensional transition metal dichalcogenides (2D TMDCs) exhibit an emerging valley pseudospin, in which spin-up (-down) electrons are distributed in a +K (-K) valley. This valley polarization gives a DOF for spintronic and valleytronic devices. Recently, magnetic exchange interactions between graphene and magnetic insulator yttrium iron garnet (YIG) have been exploited. However, the physics of 2D TMDCs with YIG have not been shown before. Here we demonstrate strong many-body effects in a heterostructure geometry comprising a MoS2 monolayer and YIG. High-order trions are directly identified by mapping absorption and photoluminescence at 12 K. The electron doping density is up to ∼1013 cm-2, resulting in a large splitting of ∼40 meV between trions and excitons. The trions exhibit a high circular polarization of ∼80% under optical pumping by circularly polarized light at ∼1.96 eV; it is confirmed experimentally that both phonon scattering and electron-hole exchange interaction contribute to the valley depolarization with temperature; importantly, a magnetoresistance (MR) behavior in the MoS2 monolayer was observed, and a giant MR ratio of ∼30% is achieved, which is 1 order of magnitude larger than the reported ratio in MoS2/CoFe2O4 heterostructures. Our experimental results confirm that the giant MR behaviors are attributed to the interfacial spin accumulation due to YIG substrates. Our work provides an insight into spin manipulation in a heterostructure of monolayer materials and magnetic substrates.
Collapse
Affiliation(s)
- Bo Peng
- National Engineering Research Center of Electromagnetic Radiation Control Materials and State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Microelectronics and Solid State Electronics, University of Electronic Science and Technology of China , Chengdu 610054, China
| | - Qi Li
- National Engineering Research Center of Electromagnetic Radiation Control Materials and State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Microelectronics and Solid State Electronics, University of Electronic Science and Technology of China , Chengdu 610054, China
| | - Xiao Liang
- National Engineering Research Center of Electromagnetic Radiation Control Materials and State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Microelectronics and Solid State Electronics, University of Electronic Science and Technology of China , Chengdu 610054, China
| | - Peng Song
- Department of Chemistry and Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore , 3 Science Drive 3, Singapore 117543
| | - Jian Li
- National Engineering Research Center of Electromagnetic Radiation Control Materials and State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Microelectronics and Solid State Electronics, University of Electronic Science and Technology of China , Chengdu 610054, China
| | - Keliang He
- IBM , Malta, New York 12020, United States
| | - Deyi Fu
- Department of Chemistry and Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore , 3 Science Drive 3, Singapore 117543
| | - Yue Li
- National Engineering Research Center of Electromagnetic Radiation Control Materials and State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Microelectronics and Solid State Electronics, University of Electronic Science and Technology of China , Chengdu 610054, China
| | - Chao Shen
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083, China
| | - Hailong Wang
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083, China
| | - Chuangtang Wang
- National Engineering Research Center of Electromagnetic Radiation Control Materials and State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Microelectronics and Solid State Electronics, University of Electronic Science and Technology of China , Chengdu 610054, China
| | - Tao Liu
- Department of Physics, Colorado State University , Fort Collins, Colorado 80523, United States
| | - Li Zhang
- National Engineering Research Center of Electromagnetic Radiation Control Materials and State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Microelectronics and Solid State Electronics, University of Electronic Science and Technology of China , Chengdu 610054, China
| | - Haipeng Lu
- National Engineering Research Center of Electromagnetic Radiation Control Materials and State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Microelectronics and Solid State Electronics, University of Electronic Science and Technology of China , Chengdu 610054, China
| | - Xin Wang
- National Engineering Research Center of Electromagnetic Radiation Control Materials and State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Microelectronics and Solid State Electronics, University of Electronic Science and Technology of China , Chengdu 610054, China
| | - Jianhua Zhao
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083, China
| | - Jianliang Xie
- National Engineering Research Center of Electromagnetic Radiation Control Materials and State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Microelectronics and Solid State Electronics, University of Electronic Science and Technology of China , Chengdu 610054, China
| | - Mingzhong Wu
- Department of Physics, Colorado State University , Fort Collins, Colorado 80523, United States
| | - Lei Bi
- National Engineering Research Center of Electromagnetic Radiation Control Materials and State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Microelectronics and Solid State Electronics, University of Electronic Science and Technology of China , Chengdu 610054, China
| | - Longjiang Deng
- National Engineering Research Center of Electromagnetic Radiation Control Materials and State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Microelectronics and Solid State Electronics, University of Electronic Science and Technology of China , Chengdu 610054, China
| | - Kian Ping Loh
- Department of Chemistry and Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore , 3 Science Drive 3, Singapore 117543
| |
Collapse
|
29
|
Abstract
We present a simplified description for spin-dependent electronic transport in honeycomb-lattice structures with spin-orbit interactions, using generalizations of the stochastic nonequilibrium model known as the totally asymmetric simple exclusion process. Mean field theory and numerical simulations are used to study currents, density profiles, and current polarization in quasi-one-dimensional systems with open boundaries, and externally imposed particle injection (α) and ejection (β) rates. We investigate the influence of allowing for double site occupancy, according to Pauli's exclusion principle, on the behavior of the quantities of interest. We find that double occupancy shows strong signatures for specific combinations of rates, namely high α and low β, but otherwise its effects are quantitatively suppressed. Comments are made on the possible relevance of the present results to experiments on suitably doped graphenelike structures.
Collapse
Affiliation(s)
- S L A de Queiroz
- Instituto de Física, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, 21941-972 Rio de Janeiro, Rio de Janeiro, Brazil
| | - R B Stinchcombe
- Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP, United Kingdom
| |
Collapse
|
30
|
Feng YP, Shen L, Yang M, Wang A, Zeng M, Wu Q, Chintalapati S, Chang CR. Prospects of spintronics based on 2D materials. WIREs Comput Mol Sci 2017. [DOI: 10.1002/wcms.1313] [Citation(s) in RCA: 101] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Yuan Ping Feng
- Department of Physics; National University of Singapore; Singapore
- Centre for Advanced Two-dimensional Materials; National University of Singapore; Singapore
| | - Lei Shen
- Department of Mechanical Engineering; National University of Singapore; Singapore
- Engineering Science Programme; National University of Singapore; Singapore
| | - Ming Yang
- Institute of Materials Science and Engineering; A*STAR; Singapore
| | - Aizhu Wang
- Department of Physics; National University of Singapore; Singapore
- Department of Electrical and Computer Engineering; National University of Singapore; Singapore
| | | | - Qingyun Wu
- Department of Materials Science and Engineering; National University of Singapore; Singapore
| | - Sandhya Chintalapati
- Centre for Advanced Two-dimensional Materials; National University of Singapore; Singapore
| | | |
Collapse
|
31
|
Song Q, Zhang H, Su T, Yuan W, Chen Y, Xing W, Shi J, Sun J, Han W. Observation of inverse Edelstein effect in Rashba-split 2DEG between SrTiO 3 and LaAlO 3 at room temperature. Sci Adv 2017; 3:e1602312. [PMID: 28345050 PMCID: PMC5357130 DOI: 10.1126/sciadv.1602312] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 02/03/2017] [Indexed: 05/14/2023]
Abstract
The Rashba physics has been intensively studied in the field of spin orbitronics for the purpose of searching novel physical properties and the ferromagnetic (FM) magnetization switching for technological applications. We report our observation of the inverse Edelstein effect up to room temperature in the Rashba-split two-dimensional electron gas (2DEG) between two insulating oxides, SrTiO3 and LaAlO3, with the LaAlO3 layer thickness from 3 to 40 unit cells (UC). We further demonstrate that the spin voltage could be markedly manipulated by electric field effect for the 2DEG between SrTiO3 and 3-UC LaAlO3. These results demonstrate that the Rashba-split 2DEG at the complex oxide interface can be used for efficient charge-and-spin conversion at room temperature for the generation and detection of spin current.
Collapse
Affiliation(s)
- Qi Song
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
| | - Hongrui Zhang
- Beijing National Laboratory for Condensed Matter Physics and the Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Tang Su
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
| | - Wei Yuan
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
| | - Yangyang Chen
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
| | - Wenyu Xing
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
| | - Jing Shi
- Department of Physics and Astronomy, University of California, Riverside, Riverside, CA 92521, USA
| | - Jirong Sun
- Beijing National Laboratory for Condensed Matter Physics and the Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Wei Han
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
| |
Collapse
|
32
|
Soumyanarayanan A, Reyren N, Fert A, Panagopoulos C. Emergent phenomena induced by spin–orbit coupling at surfaces and interfaces. Nature 2016; 539:509-517. [DOI: 10.1038/nature19820] [Citation(s) in RCA: 544] [Impact Index Per Article: 68.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 08/02/2016] [Indexed: 01/16/2023]
|
33
|
Sakai S, Majumdar S, Popov ZI, Avramov PV, Entani S, Hasegawa Y, Yamada Y, Huhtinen H, Naramoto H, Sorokin PB, Yamauchi Y. Proximity-Induced Spin Polarization of Graphene in Contact with Half-Metallic Manganite. ACS Nano 2016; 10:7532-7541. [PMID: 27438899 DOI: 10.1021/acsnano.6b02424] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The role of proximity contact with magnetic oxides is of particular interest from the expectations of the induced spin polarization and weak interactions at the graphene/magnetic oxide interfaces, which would allow us to achieve efficient spin-polarized injection in graphene-based spintronic devices. A combined approach of topmost-surface-sensitive spectroscopy utilizing spin-polarized metastable He atoms and ab initio calculations provides us direct evidence for the magnetic proximity effect in the junctions of single-layer graphene and half-metallic manganite La0.7Sr0.3MnO3 (LSMO). It is successfully demonstrated that in the graphene/LSMO junctions a sizable spin polarization is induced at the Fermi level of graphene in parallel to the spin polarization direction of LSMO without giving rise to a significant modification in the π band structure.
Collapse
Affiliation(s)
- Seiji Sakai
- Quantum Beam Science Research Directorate, National Institutes for Quantum and Radiological Science and Technology QST , 2-4 Shirakata, Tokai, Naka, Ibaraki 319-1106, Japan
- National Institute for Materials Science , Tsukuba, Ibaraki 305-0047, Japan
- Institute of Applied Physics, University of Tsukuba , 1-1-1 Tennodai, Tsukuba 305-8577, Japan
| | - Sayani Majumdar
- Department of Applied Physics, Aalto University School of Science , FI-00076 Aalto, Finland
| | - Zakhar I Popov
- National University of Science and Technology MISiS , 4 Leninskiy Prospekt, Moscow 119049, Russian Federation
| | - Pavel V Avramov
- Department of Chemistry, College of Natural Sciences, Kyungpook National University , Daegu 702-701, Republic of Korea
| | - Shiro Entani
- Quantum Beam Science Research Directorate, National Institutes for Quantum and Radiological Science and Technology QST , 2-4 Shirakata, Tokai, Naka, Ibaraki 319-1106, Japan
| | - Yuri Hasegawa
- Institute of Applied Physics, University of Tsukuba , 1-1-1 Tennodai, Tsukuba 305-8577, Japan
| | - Yoichi Yamada
- Institute of Applied Physics, University of Tsukuba , 1-1-1 Tennodai, Tsukuba 305-8577, Japan
| | - Hannu Huhtinen
- Wihuri Physical Laboratory, Department of Physics and Astronomy, University of Turku , 20014, Turku, Finland
| | - Hiroshi Naramoto
- Quantum Beam Science Research Directorate, National Institutes for Quantum and Radiological Science and Technology QST , 2-4 Shirakata, Tokai, Naka, Ibaraki 319-1106, Japan
| | - Pavel B Sorokin
- Quantum Beam Science Research Directorate, National Institutes for Quantum and Radiological Science and Technology QST , 2-4 Shirakata, Tokai, Naka, Ibaraki 319-1106, Japan
- National University of Science and Technology MISiS , 4 Leninskiy Prospekt, Moscow 119049, Russian Federation
- Technological Institute of Superhard and Novel Carbon Materials , 7a Centralnaya Street, Troitsk, Moscow 142190, Russian Federation
| | - Yasushi Yamauchi
- Quantum Beam Science Research Directorate, National Institutes for Quantum and Radiological Science and Technology QST , 2-4 Shirakata, Tokai, Naka, Ibaraki 319-1106, Japan
- National Institute for Materials Science , Tsukuba, Ibaraki 305-0047, Japan
| |
Collapse
|
34
|
Dushenko S, Ago H, Kawahara K, Tsuda T, Kuwabata S, Takenobu T, Shinjo T, Ando Y, Shiraishi M. Gate-Tunable Spin-Charge Conversion and the Role of Spin-Orbit Interaction in Graphene. Phys Rev Lett 2016; 116:166102. [PMID: 27152812 DOI: 10.1103/physrevlett.116.166102] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2015] [Indexed: 05/22/2023]
Abstract
The small spin-orbit interaction of carbon atoms in graphene promises a long spin diffusion length and the potential to create a spin field-effect transistor. However, for this reason, graphene was largely overlooked as a possible spin-charge conversion material. We report electric gate tuning of the spin-charge conversion voltage signal in single-layer graphene. Using spin pumping from an yttrium iron garnet ferrimagnetic insulator and ionic liquid top gate, we determined that the inverse spin Hall effect is the dominant spin-charge conversion mechanism in single-layer graphene. From the gate dependence of the electromotive force we showed the dominance of the intrinsic over Rashba spin-orbit interaction, a long-standing question in graphene research.
Collapse
Affiliation(s)
- S Dushenko
- Graduate School of Engineering Science, Osaka University, Toyonaka 560-8531, Japan
- Department of Electronic Science and Engineering, Kyoto University, Kyoto 615-8510, Japan
| | - H Ago
- Institute for Material Chemistry and Engineering, Kyushu University, Fukuoka 816-8508, Japan
| | - K Kawahara
- Institute for Material Chemistry and Engineering, Kyushu University, Fukuoka 816-8508, Japan
| | - T Tsuda
- Graduate School of Engineering, Osaka University, Suita 565-0871, Japan
| | - S Kuwabata
- Graduate School of Engineering, Osaka University, Suita 565-0871, Japan
| | - T Takenobu
- School of Advanced Science and Engineering, Waseda University, Tokyo 169-8555, Japan
| | - T Shinjo
- Department of Electronic Science and Engineering, Kyoto University, Kyoto 615-8510, Japan
| | - Y Ando
- Department of Electronic Science and Engineering, Kyoto University, Kyoto 615-8510, Japan
| | - M Shiraishi
- Department of Electronic Science and Engineering, Kyoto University, Kyoto 615-8510, Japan
| |
Collapse
|