中国物理B ›› 2018, Vol. 27 ›› Issue (9): 97307-097307.doi: 10.1088/1674-1056/27/9/097307

所属专题: TOPICAL REVIEW — Spin manipulation in solids

• SPECIAL TOPIC—Recent advances in thermoelectric materials and devices • 上一篇    下一篇

Electrical spin polarization through spin-momentum locking in topological-insulator nanostructures

Minhao Zhang(张敏昊), Xuefeng Wang(王学锋), Fengqi Song(宋凤麒), Rong Zhang(张荣)   

  1. 1 Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China;
    2 School of Physics, Nanjing University, Nanjing 210093, China;
    3 National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
  • 收稿日期:2018-04-29 修回日期:2018-05-18 出版日期:2018-09-05 发布日期:2018-09-05
  • 通讯作者: Xuefeng Wang, Rong Zhang E-mail:xfwang@nju.edu.cn;rzhang@nju.edu.cn
  • 基金资助:

    Project supported by the National Key Basic Research Program of China (Grant Nos. 2014CB921103 and 2017YFA0206304), the National Natural Science Foundation of China (Grant Nos. 61822403, 11874203, U1732159, and U1732273), Fundamental Research Funds for the Central Universities, China (Grant No. 021014380080), and Collaborative Innovation Center of Solid-State Lighting and Energy-Saving Electronics, China.

Electrical spin polarization through spin-momentum locking in topological-insulator nanostructures

Minhao Zhang(张敏昊)1, Xuefeng Wang(王学锋)1,3, Fengqi Song(宋凤麒)2,3, Rong Zhang(张荣)1,3   

  1. 1 Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China;
    2 School of Physics, Nanjing University, Nanjing 210093, China;
    3 National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
  • Received:2018-04-29 Revised:2018-05-18 Online:2018-09-05 Published:2018-09-05
  • Contact: Xuefeng Wang, Rong Zhang E-mail:xfwang@nju.edu.cn;rzhang@nju.edu.cn
  • Supported by:

    Project supported by the National Key Basic Research Program of China (Grant Nos. 2014CB921103 and 2017YFA0206304), the National Natural Science Foundation of China (Grant Nos. 61822403, 11874203, U1732159, and U1732273), Fundamental Research Funds for the Central Universities, China (Grant No. 021014380080), and Collaborative Innovation Center of Solid-State Lighting and Energy-Saving Electronics, China.

摘要:

Recently, spin-momentum-locked topological surface states (SSs) have attracted significant attention in spintronics. Owing to spin-momentum locking, the direction of the spin is locked at right angles with respect to the carrier momentum. In this paper, we briefly review the exotic transport properties induced by topological SSs in topological-insulator (TI) nanostructures, which have larger surface-to-volume ratios than those of bulk TI materials. We discuss the electrical spin generation in TIs and its effect on the transport properties. A current flow can generate a pure in-plane spin polarization on the surface, leading to a current-direction-dependent magnetoresistance in spin valve devices based on TI nanostructures. A relative momentum shift of two coupled topological SSs also generates net spin polarization and induces an in-plane anisotropic negative magnetoresistance. Therefore, the spin-momentum locking can enable the broad tuning of the spin transport properties of topological devices for spintronic applications.

关键词: spin-momentum locking, electrical spin generation, topological insulators, topological devices, spintronics

Abstract:

Recently, spin-momentum-locked topological surface states (SSs) have attracted significant attention in spintronics. Owing to spin-momentum locking, the direction of the spin is locked at right angles with respect to the carrier momentum. In this paper, we briefly review the exotic transport properties induced by topological SSs in topological-insulator (TI) nanostructures, which have larger surface-to-volume ratios than those of bulk TI materials. We discuss the electrical spin generation in TIs and its effect on the transport properties. A current flow can generate a pure in-plane spin polarization on the surface, leading to a current-direction-dependent magnetoresistance in spin valve devices based on TI nanostructures. A relative momentum shift of two coupled topological SSs also generates net spin polarization and induces an in-plane anisotropic negative magnetoresistance. Therefore, the spin-momentum locking can enable the broad tuning of the spin transport properties of topological devices for spintronic applications.

Key words: spin-momentum locking, electrical spin generation, topological insulators, topological devices, spintronics

中图分类号:  (Galvanomagnetic and other magnetotransport effects)

  • 73.50.Jt
05.30.Rt (Quantum phase transitions)