中国物理B ›› 2022, Vol. 31 ›› Issue (9): 97302-097302.doi: 10.1088/1674-1056/ac5d2b

• • 上一篇    下一篇

Current carrying states in the disordered quantum anomalous Hall effect

Yi-Ming Dai(戴镒明)1,2, Si-Si Wang(王思思)1,2,3, Yan Yu(禹言)4,5, Ji-Huan Guan(关济寰)6,4, Hui-Hui Wang(王慧慧)1,7,2, and Yan-Yang Zhang(张艳阳)1,7,2,3,†   

  1. 1 School of Physics and Materials Science, Guangzhou University, Guangzhou 510006, China;
    2 Research Center for Advanced Information Materials, Guangzhou University, Guangzhou 510006, China;
    3 School of Mathematics and Information Science, Guangzhou University, Guangzhou 510006, China;
    4 SKLSM, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China;
    5 School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China;
    6 Beijing Academy of Quantum Information Sciences, Beijing 100193, China;
    7 Huangpu Research and Graduate School of Guangzhou University, Guangzhou 510700, China
  • 收稿日期:2022-01-13 修回日期:2022-03-04 接受日期:2022-03-14 出版日期:2022-08-19 发布日期:2022-09-03
  • 通讯作者: Yan-Yang Zhang E-mail:yanyang@gzhu.edu.cn
  • 基金资助:
    This work was supported by the National Natural Science Foundation of China (Grant Nos. 11774336, 12104108, and 61427901) and the Starting Research Fund from Guangzhou University (Grant Nos. RQ2020082 and 62104360).

Current carrying states in the disordered quantum anomalous Hall effect

Yi-Ming Dai(戴镒明)1,2, Si-Si Wang(王思思)1,2,3, Yan Yu(禹言)4,5, Ji-Huan Guan(关济寰)6,4, Hui-Hui Wang(王慧慧)1,7,2, and Yan-Yang Zhang(张艳阳)1,7,2,3,†   

  1. 1 School of Physics and Materials Science, Guangzhou University, Guangzhou 510006, China;
    2 Research Center for Advanced Information Materials, Guangzhou University, Guangzhou 510006, China;
    3 School of Mathematics and Information Science, Guangzhou University, Guangzhou 510006, China;
    4 SKLSM, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China;
    5 School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China;
    6 Beijing Academy of Quantum Information Sciences, Beijing 100193, China;
    7 Huangpu Research and Graduate School of Guangzhou University, Guangzhou 510700, China
  • Received:2022-01-13 Revised:2022-03-04 Accepted:2022-03-14 Online:2022-08-19 Published:2022-09-03
  • Contact: Yan-Yang Zhang E-mail:yanyang@gzhu.edu.cn
  • Supported by:
    This work was supported by the National Natural Science Foundation of China (Grant Nos. 11774336, 12104108, and 61427901) and the Starting Research Fund from Guangzhou University (Grant Nos. RQ2020082 and 62104360).

摘要: In a quantum Hall effect, flat Landau levels may be broadened by disorder. However, it has been found that in the thermodynamic limit, all extended (or current carrying) states shrink to one single energy value within each Landau level. On the other hand, a quantum anomalous Hall effect consists of dispersive bands with finite widths. We numerically investigate the picture of current carrying states in this case. With size scaling, the spectrum width of these states in each bulk band still shrinks to a single energy value in the thermodynamic limit, in a power law way. The magnitude of the scaling exponent at the intermediate disorder is close to that in the quantum Hall effects. The number of current carrying states obeys similar scaling rules, so that the density of states of current carrying states is finite. Other states in the bulk band are localized and may contribute to the formation of a topological Anderson insulator.

关键词: quantum anomalous Hall effect, Chern number, disordered system, localization

Abstract: In a quantum Hall effect, flat Landau levels may be broadened by disorder. However, it has been found that in the thermodynamic limit, all extended (or current carrying) states shrink to one single energy value within each Landau level. On the other hand, a quantum anomalous Hall effect consists of dispersive bands with finite widths. We numerically investigate the picture of current carrying states in this case. With size scaling, the spectrum width of these states in each bulk band still shrinks to a single energy value in the thermodynamic limit, in a power law way. The magnitude of the scaling exponent at the intermediate disorder is close to that in the quantum Hall effects. The number of current carrying states obeys similar scaling rules, so that the density of states of current carrying states is finite. Other states in the bulk band are localized and may contribute to the formation of a topological Anderson insulator.

Key words: quantum anomalous Hall effect, Chern number, disordered system, localization

中图分类号:  (Weak or Anderson localization)

  • 73.20.Fz
73.43.-f (Quantum Hall effects) 74.62.En (Effects of disorder)