Metal-to-insulator switching in quantum anomalous Hall states

ORAL

Abstract

Quantum anomalous Hall effect (QAHE) was recently achieved in magnetic topological insulator films as a form of dissipationless transport without external magnetic field. However, the universal phase diagram of QAHE and its relation with quantum Hall effect (QHE) remain to be investigated. Here, we report the experimental observation of the giant longitudinal resistance peak and zero Hall conductance plateau at the coercive field in the six quintuple-layer (Cr$_{0.12}$Bi$_{0.26}$Sb$_{0.62})_{2}$Te$_{3}$ film, and demonstrate the metal-to-insulator switching between two opposite QAHE plateau states up to 0.3 K. The universal QAHE phase diagram is further confirmed through the angle-dependent measurements. Our results address that the quantum phase transitions in both QAHE and QHE regimes are in the same universality class, yet the microscopic details are different.

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Authors

  • Lei Pan

    Univ of California - Los Angeles

  • Xufeng Kou

    Univ of California - Los Angeles

  • Jing Wang

    stanford university

  • Yabin Fan

    Electrical Engineering, UCLA, Univ of California - Los Angeles, University of California, Los Angeles

  • Eun Sang Choi

    National High Magnetic Field Laboratory, Florida State University

  • Qiming Shao

    Univ of California - Los Angeles

  • Shou-Cheng Zhang

    Department of Physics, Stanford University, stanford university, Stanford University, Stanford Univ

  • Kang Wang

    UCLA, Electrical Engineering, UCLA, Univ of California - Los Angeles, University of California, Los Angeles