1
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Guo L, Hu S, Gu X, Zhang R, Wang K, Yan W, Sun X. Emerging Spintronic Materials and Functionalities. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2301854. [PMID: 37309258 DOI: 10.1002/adma.202301854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 06/01/2023] [Indexed: 06/14/2023]
Abstract
The explosive growth of the information era has put forward urgent requirements for ultrahigh-speed and extremely efficient computations. In direct contrary to charge-based computations, spintronics aims to use spins as information carriers for data storage, transmission, and decoding, to help fully realize electronic device miniaturization and high integration for next-generation computing technologies. Currently, many novel spintronic materials have been developed with unique properties and multifunctionalities, including organic semiconductors (OSCs), organic-inorganic hybrid perovskites (OIHPs), and 2D materials (2DMs). These materials are useful to fulfill the demand for developing diverse and advanced spintronic devices. Herein, these promising materials are systematically reviewed for advanced spintronic applications. Due to the distinct chemical and physical structures of OSCs, OIHPs, and 2DMs, their spintronic properties (spin transport and spin manipulation) are discussed separately. In addition, some multifunctionalities due to photoelectric and chiral-induced spin selectivity (CISS) are overviewed, including the spin-filter effect, spin-photovoltaics, spin-light emitting devices, and spin-transistor functions. Subsequently, challenges and future perspectives of using these multifunctional materials for the development of advanced spintronics are presented.
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Affiliation(s)
- Lidan Guo
- Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China
| | - Shunhua Hu
- Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Xianrong Gu
- Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China
| | - Rui Zhang
- Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China
| | - Kai Wang
- Key Laboratory of Luminescence and Optical Information, Ministry of Education, School of Physical Science and Engineering, Institute of Optoelectronics Technology, Beijing Jiaotong University, Beijing, 100044, P. R. China
| | - Wenjing Yan
- School of Physics and Astronomy, University of Nottingham, University Park, Nottingham, NG9 2RD, UK
| | - Xiangnan Sun
- Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
- School of Material Science and Engineering, Zhengzhou University, Zhengzhou, 450001, P. R. China
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2
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Bloom BP, Paltiel Y, Naaman R, Waldeck DH. Chiral Induced Spin Selectivity. Chem Rev 2024; 124:1950-1991. [PMID: 38364021 PMCID: PMC10906005 DOI: 10.1021/acs.chemrev.3c00661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 01/16/2024] [Accepted: 01/23/2024] [Indexed: 02/18/2024]
Abstract
Since the initial landmark study on the chiral induced spin selectivity (CISS) effect in 1999, considerable experimental and theoretical efforts have been made to understand the physical underpinnings and mechanistic features of this interesting phenomenon. As first formulated, the CISS effect refers to the innate ability of chiral materials to act as spin filters for electron transport; however, more recent experiments demonstrate that displacement currents arising from charge polarization of chiral molecules lead to spin polarization without the need for net charge flow. With its identification of a fundamental connection between chiral symmetry and electron spin in molecules and materials, CISS promises profound and ubiquitous implications for existing technologies and new approaches to answering age old questions, such as the homochiral nature of life. This review begins with a discussion of the different methods for measuring CISS and then provides a comprehensive overview of molecules and materials known to exhibit CISS-based phenomena before proceeding to identify structure-property relations and to delineate the leading theoretical models for the CISS effect. Next, it identifies some implications of CISS in physics, chemistry, and biology. The discussion ends with a critical assessment of the CISS field and some comments on its future outlook.
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Affiliation(s)
- Brian P. Bloom
- Department
of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Yossi Paltiel
- Applied
Physics Department and Center for Nano-Science and Nano-Technology, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Ron Naaman
- Department
of Chemical and Biological Physics, Weizmann
Institute, Rehovot 76100, Israel
| | - David H. Waldeck
- Department
of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
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3
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Sutter P, Unocic RR, Sutter E. Tuning of Single Mixed (Helical) Dislocations in Core-Shell van der Waals Nanowires. J Am Chem Soc 2023; 145:20503-20510. [PMID: 37695639 DOI: 10.1021/jacs.3c06469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Linear defects (dislocations) not only govern the mechanical properties of crystalline solids but they can also produce distinct electronic, thermal, and topological effects. Accessing this functionality requires control over the placement and geometry of single dislocations embedded in a small host volume to maximize emerging effects. Here we identify a synthetic route for rational dislocation placement and tuning in van der Waals nanowires, where the layered crystal limits the possible defect configurations and the nanowire architecture puts single dislocations in close proximity to the entire host volume. While homogeneous layered nanowires host single screw dislocations, the synthesis of radial nanowire heterostructures (here exemplified by GeS-Ge1-xSnxS monochalcogenide core-shell nanowires) transforms the defect into a mixed (helical) dislocation whose edge/screw ratio is tunable via the core-shell lattice mismatch. The ability to design nanomaterials with control over individual mixed dislocations paves the way for identifying the functional properties of dislocations and harnessing them in technology.
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Affiliation(s)
- Peter Sutter
- Department of Electrical & Computer Engineering, University of Nebraska─Lincoln, Lincoln, Nebraska 68588, United States
| | - Raymond R Unocic
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Eli Sutter
- Department of Mechanical & Materials Engineering, University of Nebraska─Lincoln, Lincoln, Nebraska 68588, United States
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4
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Xu S, Dai B, Cheng H, Tai L, Lang L, Sun Y, Shi Z, Wang KL, Zhao W. Electric-Field Control of Spin Diffusion Length and Electric-Assisted D'yakonov-Perel' Mechanism in Ultrathin Heavy Metal and Ferromagnetic Insulator Heterostructure. MATERIALS (BASEL, SWITZERLAND) 2022; 15:6368. [PMID: 36143680 PMCID: PMC9501297 DOI: 10.3390/ma15186368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 09/07/2022] [Accepted: 09/08/2022] [Indexed: 06/16/2023]
Abstract
Electric-field control of spin dynamics is significant for spintronic device applications. Thus far, effectively electric-field control of magnetic order, magnetic damping factor and spin-orbit torque (SOT) has been studied in magnetic materials, but the electric field control of spin relaxation still remains unexplored. Here, we use ionic liquid gating to control spin-related property in the ultra-thin (4 nm) heavy metal (HM) platinum (Pt) and ferromagnetic insulator (FMI) yttrium iron garnet (Y3Fe5O12, YIG) heterostructure. It is found that the anomalous Hall effect (AHE), spin relaxation time and spin diffusion length can be effectively controlled by the electric field. The anomalous Hall resistance is almost twice as large as at 0 voltage after applying a small voltage of 5.5 V. The spin relaxation time can vary by more than 50 percent with the electric field, from 41.6 to 64.5 fs. In addition, spin relaxation time at different gate voltage follows the reciprocal law of the electron momentum scattering time, which indicates that the D'yakonov-Perel' mechanism is dominant in the Pt/YIG system. Furthermore, the spin diffusion length can be effectively controlled by an ionic gate, which can be well explained by voltage-modulated interfacial spin scattering. These results help us to improve the interface spin transport properties in magnetic materials, with great contributions to the exploration of new physical mechanisms and spintronics device.
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Affiliation(s)
- Shijie Xu
- Fert Beijing Institute, Ministry of Industry and Information Technology Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China
- Department of Electrical and Computer Engineering, University of California, Los Angeles, CA 90095, USA
- Shanghai Key Laboratory of Special Artificial Microstructure, Pohl Institute of Solid State Physics, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
- Hefei Innovation Research Institute, Anhui High Reliability Chips Engineering Laboratory, Beihang University, Hefei 230013, China
| | - Bingqian Dai
- Department of Electrical and Computer Engineering, University of California, Los Angeles, CA 90095, USA
| | - Houyi Cheng
- Fert Beijing Institute, Ministry of Industry and Information Technology Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China
- Hefei Innovation Research Institute, Anhui High Reliability Chips Engineering Laboratory, Beihang University, Hefei 230013, China
| | - Lixuan Tai
- Department of Electrical and Computer Engineering, University of California, Los Angeles, CA 90095, USA
| | - Lili Lang
- Shanghai Key Laboratory of Special Artificial Microstructure, Pohl Institute of Solid State Physics, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
| | - Yadong Sun
- Shanghai Key Laboratory of Special Artificial Microstructure, Pohl Institute of Solid State Physics, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
| | - Zhong Shi
- Shanghai Key Laboratory of Special Artificial Microstructure, Pohl Institute of Solid State Physics, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
| | - Kang L. Wang
- Department of Electrical and Computer Engineering, University of California, Los Angeles, CA 90095, USA
| | - Weisheng Zhao
- Fert Beijing Institute, Ministry of Industry and Information Technology Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China
- Hefei Innovation Research Institute, Anhui High Reliability Chips Engineering Laboratory, Beihang University, Hefei 230013, China
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5
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Vila M, Garcia JH, Cummings AW, Power SR, Groth CW, Waintal X, Roche S. Nonlocal Spin Dynamics in the Crossover from Diffusive to Ballistic Transport. PHYSICAL REVIEW LETTERS 2020; 124:196602. [PMID: 32469541 DOI: 10.1103/physrevlett.124.196602] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 04/27/2020] [Indexed: 06/11/2023]
Abstract
Improved fabrication techniques have enabled the possibility of ballistic transport and unprecedented spin manipulation in ultraclean graphene devices. Spin transport in graphene is typically probed in a nonlocal spin valve and is analyzed using spin diffusion theory, but this theory is not necessarily applicable when charge transport becomes ballistic or when the spin diffusion length is exceptionally long. Here, we study these regimes by performing quantum simulations of graphene nonlocal spin valves. We find that conventional spin diffusion theory fails to capture the crossover to the ballistic regime as well as the limit of long spin diffusion length. We show that the latter can be described by an extension of the current theoretical framework. Finally, by covering the whole range of spin dynamics, our study opens a new perspective to predict and scrutinize spin transport in graphene and other two-dimensional material-based ultraclean devices.
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Affiliation(s)
- Marc Vila
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain
- Department of Physics, Universitat Autònoma de Barcelona, Campus UAB, Bellaterra, 08193 Barcelona, Spain
| | - Jose H Garcia
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain
| | - Aron W Cummings
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain
| | - Stephen R Power
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain
- Universitat Autònoma de Barcelona, Campus UAB, Bellaterra, 08193 Barcelona, Spain
- School of Physics, Trinity College Dublin, Dublin 2, Ireland
| | - Christoph W Groth
- Université Grenoble Alpes, CEA, IRIG-PHELIQS, 38000 Grenoble, France
| | - Xavier Waintal
- Université Grenoble Alpes, CEA, IRIG-PHELIQS, 38000 Grenoble, France
| | - Stephan Roche
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain
- ICREA-Institució Catalana de Recerca i Estudis Avançats, 08010 Barcelona, Spain
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6
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Kountouriotis K, Barreda JL, Keiper TD, Zhang M, Xiong P. Electrical Spin Injection and Detection in Silicon Nanowires with Axial Doping Gradient. NANO LETTERS 2018; 18:4386-4395. [PMID: 29898367 DOI: 10.1021/acs.nanolett.8b01423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The interest in spin transport in nanoscopic semiconductor channels is driven by both the inevitable miniaturization of spintronics devices toward nanoscale and the rich spin-dependent physics the quantum confinement engenders. For such studies, the all-important issue of the ferromagnet/semiconductor (FM/SC) interface becomes even more critical at nanoscale. Here we elucidate the effects of the FM/SC interface on electrical spin injection and detection at nanoscale dimensions, utilizing a unique type of Si nanowires (NWs) with an inherent axial doping gradient. Two-terminal and nonlocal four-terminal lateral spin-valve measurements were performed using different combinations from a series of FM contacts positioned along the same NW. The data are analyzed with a general model of spin accumulation in a normal channel under electrical spin injection from a FM, which reveals a distinct correlation of decreasing spin-valve signal with increasing injector junction resistance. The observation is attributed to the diminishing contribution of the d-electrons in the FM to the injected current spin polarization with increasing Schottky barrier width. The results demonstrate that there is a window of interface parameters for optimal spin injection efficiency and current spin polarization, which provides important design guidelines for nanospintronic devices with quasi-one-dimensional semiconductor channels.
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Affiliation(s)
| | - Jorge L Barreda
- Department of Physics , Florida State University , Tallahassee , Florida 32306 , United States
| | - Timothy D Keiper
- Department of Physics , Florida State University , Tallahassee , Florida 32306 , United States
| | - Mei Zhang
- Department of Industrial and Manufacturing Engineering, College of Engineering , Florida A&M University-Florida State University (FAMU-FSU) , Tallahassee , Florida 32310 , United States
| | - Peng Xiong
- Department of Physics , Florida State University , Tallahassee , Florida 32306 , United States
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7
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Park TE, Park YH, Lee JM, Kim SW, Park HG, Min BC, Kim HJ, Koo HC, Choi HJ, Han SH, Johnson M, Chang J. Large spin accumulation and crystallographic dependence of spin transport in single crystal gallium nitride nanowires. Nat Commun 2017; 8:15722. [PMID: 28569767 PMCID: PMC5461503 DOI: 10.1038/ncomms15722] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 04/24/2017] [Indexed: 11/09/2022] Open
Abstract
Semiconductor spintronics is an alternative to conventional electronics that offers devices with high performance, low power and multiple functionality. Although a large number of devices with mesoscopic dimensions have been successfully demonstrated at low temperatures for decades, room-temperature operation still needs to go further. Here we study spin injection in single-crystal gallium nitride nanowires and report robust spin accumulation at room temperature with enhanced spin injection polarization of 9%. A large Overhauser coupling between the electron spin accumulation and the lattice nuclei is observed. Finally, our single-crystal gallium nitride samples have a trigonal cross-section defined by the (001), () and () planes. Using the Hanle effect, we show that the spin accumulation is significantly different for injection across the (001) and () (or ()) planes. This provides a technique for increasing room temperature spin injection in mesoscopic systems.
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Affiliation(s)
- Tae-Eon Park
- Center for Spintronics, Post-Si Semiconductor Institute, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 02792, Korea
| | - Youn Ho Park
- Center for Spintronics, Post-Si Semiconductor Institute, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 02792, Korea.,Department of Materials Science and Engineering, Yonsei University, Seoul 03722, Korea
| | - Jong-Min Lee
- Center for Spintronics, Post-Si Semiconductor Institute, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 02792, Korea
| | - Sung Wook Kim
- Department of Materials Science and Engineering, Yonsei University, Seoul 03722, Korea
| | - Hee Gyum Park
- Center for Spintronics, Post-Si Semiconductor Institute, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 02792, Korea.,Department of Nanomaterials Science and Engineering, Korea University of Science and Technology, Daejeon 34113, Korea
| | - Byoung-Chul Min
- Center for Spintronics, Post-Si Semiconductor Institute, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 02792, Korea.,Department of Nanomaterials Science and Engineering, Korea University of Science and Technology, Daejeon 34113, Korea
| | - Hyung-Jun Kim
- Center for Spintronics, Post-Si Semiconductor Institute, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 02792, Korea
| | - Hyun Cheol Koo
- Center for Spintronics, Post-Si Semiconductor Institute, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 02792, Korea.,KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Korea
| | - Heon-Jin Choi
- Department of Materials Science and Engineering, Yonsei University, Seoul 03722, Korea
| | - Suk Hee Han
- Center for Spintronics, Post-Si Semiconductor Institute, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 02792, Korea
| | - Mark Johnson
- Naval Research Laboratory, Washington, District Of Columbia 20375, USA
| | - Joonyeon Chang
- Center for Spintronics, Post-Si Semiconductor Institute, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 02792, Korea.,Department of Nanomaterials Science and Engineering, Korea University of Science and Technology, Daejeon 34113, Korea
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8
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Computational Predictions for Single Chain Chalcogenide-Based One-Dimensional Materials. NANOMATERIALS 2017; 7:nano7050115. [PMID: 28513537 PMCID: PMC5449996 DOI: 10.3390/nano7050115] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 04/24/2017] [Accepted: 05/02/2017] [Indexed: 11/24/2022]
Abstract
Exfoliation of multilayered materials has led to an abundance of new two-dimensional (2D) materials and to their fabrication by other means. These materials have shown exceptional promise for many applications. In a similar fashion, we can envision starting with crystalline polymeric (multichain) materials and exfoliate single-chain, one-dimensional (1D) materials that may also prove useful. We use electronic structure methods to elucidate the properties of such 1D materials: individual chains of chalcogens, of silicon dichalcogenides and of sulfur nitrides. The results indicate reasonable exfoliation energies in the case of polymeric three-dimensional (3D) materials. Quantum confinement effects lead to large band gaps and large exciton binding energies. The effects of strain are quantified and heterojunction band offsets are determined. Possible applications would entail 1D materials on 3D or 2D substrates.
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9
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Jariwala D, Marks TJ, Hersam MC. Mixed-dimensional van der Waals heterostructures. NATURE MATERIALS 2017; 16:170-181. [PMID: 27479211 DOI: 10.1038/nmat4703] [Citation(s) in RCA: 561] [Impact Index Per Article: 80.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 06/21/2016] [Indexed: 05/18/2023]
Abstract
The isolation of a growing number of two-dimensional (2D) materials has inspired worldwide efforts to integrate distinct 2D materials into van der Waals (vdW) heterostructures. Given that any passivated, dangling-bond-free surface will interact with another through vdW forces, the vdW heterostructure concept can be extended to include the integration of 2D materials with non-2D materials that adhere primarily through non-covalent interactions. We present a succinct and critical survey of emerging mixed-dimensional (2D + nD, where n is 0, 1 or 3) heterostructure devices. By comparing and contrasting with all-2D vdW heterostructures as well as with competing conventional technologies, we highlight the challenges and opportunities for mixed-dimensional vdW heterostructures.
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Affiliation(s)
- Deep Jariwala
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, USA
| | - Tobin J Marks
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, USA
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA
| | - Mark C Hersam
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, USA
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA
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10
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Cobas ED, van 't Erve OMJ, Cheng SF, Culbertson JC, Jernigan GG, Bussman K, Jonker BT. Room-Temperature Spin Filtering in Metallic Ferromagnet-Multilayer Graphene-Ferromagnet Junctions. ACS NANO 2016; 10:10357-10365. [PMID: 27806204 DOI: 10.1021/acsnano.6b06092] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We report room-temperature negative magnetoresistance in ferromagnet-graphene-ferromagnet (FM|Gr|FM) junctions with minority spin polarization exceeding 80%, consistent with predictions of strong minority spin filtering. We fabricated arrays of such junctions via chemical vapor deposition of multilayer graphene on lattice-matched single-crystal NiFe(111) films and standard photolithographic patterning and etching techniques. The junctions exhibit metallic transport behavior, low resistance, and the negative magnetoresistance characteristic of a minority spin filter interface throughout the temperature range 10 to 300 K. We develop a device model to incorporate the predicted spin filtering by explicitly treating a metallic minority spin channel with spin current conversion and a tunnel barrier majority spin channel and extract spin polarization of at least 80% in the graphene layer in our structures. The junctions also show antiferromagnetic coupling, consistent with several recent predictions. The methods and findings are relevant to fast-readout low-power magnetic random access memory technology, spin logic devices, and low-power magnetic field sensors.
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Affiliation(s)
- Enrique D Cobas
- Naval Research Laboratory , 4555 Overlook Avenue SW, Washington D.C. 20375, United States
| | - Olaf M J van 't Erve
- Naval Research Laboratory , 4555 Overlook Avenue SW, Washington D.C. 20375, United States
| | - Shu-Fan Cheng
- Naval Research Laboratory , 4555 Overlook Avenue SW, Washington D.C. 20375, United States
| | - James C Culbertson
- Naval Research Laboratory , 4555 Overlook Avenue SW, Washington D.C. 20375, United States
| | - Glenn G Jernigan
- Naval Research Laboratory , 4555 Overlook Avenue SW, Washington D.C. 20375, United States
| | - Konrad Bussman
- Naval Research Laboratory , 4555 Overlook Avenue SW, Washington D.C. 20375, United States
| | - Berend T Jonker
- Naval Research Laboratory , 4555 Overlook Avenue SW, Washington D.C. 20375, United States
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11
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Averyanov DV, Tokmachev AM, Karateeva CG, Karateev IA, Lobanovich EF, Prutskov GV, Parfenov OE, Taldenkov AN, Vasiliev AL, Storchak VG. Europium Silicide - a Prospective Material for Contacts with Silicon. Sci Rep 2016; 6:25980. [PMID: 27211700 PMCID: PMC4876492 DOI: 10.1038/srep25980] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 04/26/2016] [Indexed: 11/25/2022] Open
Abstract
Metal-silicon junctions are crucial to the operation of semiconductor devices: aggressive scaling demands low-resistive metallic terminals to replace high-doped silicon in transistors. It suggests an efficient charge injection through a low Schottky barrier between a metal and Si. Tremendous efforts invested into engineering metal-silicon junctions reveal the major role of chemical bonding at the interface: premier contacts entail epitaxial integration of metal silicides with Si. Here we present epitaxially grown EuSi2/Si junction characterized by RHEED, XRD, transmission electron microscopy, magnetization and transport measurements. Structural perfection leads to superb conductivity and a record-low Schottky barrier with n-Si while an antiferromagnetic phase invites spin-related applications. This development opens brand-new opportunities in electronics.
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Affiliation(s)
- Dmitry V Averyanov
- National Research Center "Kurchatov Institute", Kurchatov Square 1, Moscow 123182, Russia
| | - Andrey M Tokmachev
- National Research Center "Kurchatov Institute", Kurchatov Square 1, Moscow 123182, Russia
| | - Christina G Karateeva
- National Research Center "Kurchatov Institute", Kurchatov Square 1, Moscow 123182, Russia
| | - Igor A Karateev
- National Research Center "Kurchatov Institute", Kurchatov Square 1, Moscow 123182, Russia
| | - Eduard F Lobanovich
- National Research Center "Kurchatov Institute", Kurchatov Square 1, Moscow 123182, Russia
| | - Grigory V Prutskov
- National Research Center "Kurchatov Institute", Kurchatov Square 1, Moscow 123182, Russia
| | - Oleg E Parfenov
- National Research Center "Kurchatov Institute", Kurchatov Square 1, Moscow 123182, Russia
| | - Alexander N Taldenkov
- National Research Center "Kurchatov Institute", Kurchatov Square 1, Moscow 123182, Russia
| | - Alexander L Vasiliev
- National Research Center "Kurchatov Institute", Kurchatov Square 1, Moscow 123182, Russia
| | - Vyacheslav G Storchak
- National Research Center "Kurchatov Institute", Kurchatov Square 1, Moscow 123182, Russia
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12
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Modepalli V, Jin MJ, Park J, Jo J, Kim JH, Baik JM, Seo C, Kim J, Yoo JW. Gate-Tunable Spin Exchange Interactions and Inversion of Magnetoresistance in Single Ferromagnetic ZnO Nanowires. ACS NANO 2016; 10:4618-4626. [PMID: 26964013 DOI: 10.1021/acsnano.6b00921] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Electrical control of ferromagnetism in semiconductor nanostructures offers the promise of nonvolatile functionality in future semiconductor spintronics. Here, we demonstrate a dramatic gate-induced change of ferromagnetism in ZnO nanowire (NW) field-effect transistors (FETs). Ferromagnetism in our ZnO NWs arose from oxygen vacancies, which constitute deep levels hosting unpaired electron spins. The magnetic transition temperature of the studied ZnO NWs was estimated to be well above room temperature. The in situ UV confocal photoluminescence (PL) study confirmed oxygen vacancy mediated ferromagnetism in the studied ZnO NW FET devices. Both the estimated carrier concentration and temperature-dependent conductivity reveal the studied ZnO NWs are at the crossover of the metal-insulator transition. In particular, gate-induced modulation of the carrier concentration in the ZnO NW FET significantly alters carrier-mediated exchange interactions, which causes even inversion of magnetoresistance (MR) from negative to positive values. Upon sweeping the gate bias from -40 to +50 V, the MRs estimated at 2 K and 2 T were changed from -11.3% to +4.1%. Detailed analysis on the gate-dependent MR behavior clearly showed enhanced spin splitting energy with increasing carrier concentration. Gate-voltage-dependent PL spectra of an individual NW device confirmed the localization of oxygen vacancy-induced spins, indicating that gate-tunable indirect exchange coupling between localized magnetic moments played an important role in the remarkable change of the MR.
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Affiliation(s)
- Vijayakumar Modepalli
- School of Materials Science and Engineering-Low dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology , Ulsan 689-798, Republic of Korea
| | - Mi-Jin Jin
- School of Materials Science and Engineering-Low dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology , Ulsan 689-798, Republic of Korea
| | - Jungmin Park
- School of Materials Science and Engineering-Low dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology , Ulsan 689-798, Republic of Korea
| | - Junhyeon Jo
- School of Materials Science and Engineering-Low dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology , Ulsan 689-798, Republic of Korea
| | - Ji-Hyun Kim
- School of Materials Science and Engineering-Low dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology , Ulsan 689-798, Republic of Korea
| | - Jeong Min Baik
- School of Materials Science and Engineering-Low dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology , Ulsan 689-798, Republic of Korea
| | - Changwon Seo
- Center for Integrated Nanostructure Physics, Institute for Basic Science, Sungkyunkwan University , Suwon 440-746, Republic of Korea
- Department of Energy Science, Sungkyunkwan University , Suwon 440-746, Republic of Korea
| | - Jeongyong Kim
- Center for Integrated Nanostructure Physics, Institute for Basic Science, Sungkyunkwan University , Suwon 440-746, Republic of Korea
- Department of Energy Science, Sungkyunkwan University , Suwon 440-746, Republic of Korea
| | - Jung-Woo Yoo
- School of Materials Science and Engineering-Low dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology , Ulsan 689-798, Republic of Korea
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