中国物理B ›› 2015, Vol. 24 ›› Issue (12): 127301-127301.doi: 10.1088/1674-1056/24/12/127301

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Spin-valley quantum Hall phases in graphene

田宏玉   

  1. Department of Physics, Yancheng Institute of Technology, Yancheng 224051, China
  • 收稿日期:2015-06-26 修回日期:2015-08-06 出版日期:2015-12-05 发布日期:2015-12-05
  • 通讯作者: Tian Hong-Yu E-mail:tianhy2010@163.com
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11447218, 11274059, 11404278, and 11447216).

Spin-valley quantum Hall phases in graphene

Tian Hong-Yu (田宏玉)   

  1. Department of Physics, Yancheng Institute of Technology, Yancheng 224051, China
  • Received:2015-06-26 Revised:2015-08-06 Online:2015-12-05 Published:2015-12-05
  • Contact: Tian Hong-Yu E-mail:tianhy2010@163.com
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11447218, 11274059, 11404278, and 11447216).

摘要: We theoretically investigate possible quantum Hall phases and corresponding edge states in graphene by taking a strong magnetic field, Zeeman splitting M, and sublattice potential Δ into account but without spin-orbit interaction. It was found that for the undoped graphene either a quantum valley Hall phase or a quantum spin Hall phase emerges in the system, depending on relative magnitudes of M and Δ . When the Fermi energy deviates from the Dirac point, the quantum spin-valley Hall phase appears and its characteristic edge state is contributed only by one spin and one valley species. The metallic boundary states bridging different quantum Hall phases possess a half-integer quantized conductance, like e2/2h or 3e2/2h. The possibility of tuning different quantum Hall states with M and Δ suggests possible graphene-based spintronics and valleytronics applications.

关键词: quantum Hall phases, graphene, magnetic field, metallic boundary states

Abstract: We theoretically investigate possible quantum Hall phases and corresponding edge states in graphene by taking a strong magnetic field, Zeeman splitting M, and sublattice potential Δ into account but without spin-orbit interaction. It was found that for the undoped graphene either a quantum valley Hall phase or a quantum spin Hall phase emerges in the system, depending on relative magnitudes of M and Δ . When the Fermi energy deviates from the Dirac point, the quantum spin-valley Hall phase appears and its characteristic edge state is contributed only by one spin and one valley species. The metallic boundary states bridging different quantum Hall phases possess a half-integer quantized conductance, like e2/2h or 3e2/2h. The possibility of tuning different quantum Hall states with M and Δ suggests possible graphene-based spintronics and valleytronics applications.

Key words: quantum Hall phases, graphene, magnetic field, metallic boundary states

中图分类号:  (Surface states, band structure, electron density of states)

  • 73.20.At
72.25.Dc (Spin polarized transport in semiconductors) 73.22.Pr (Electronic structure of graphene) 73.43.Nq (Quantum phase transitions)