Scanning SQUID Microscopy of the Quantum Anomalous Hall Effect

ORAL

Abstract

We report magnetic imaging of Cr-doped (Bi,Sb)2Te3 heterostructures in the quantum anomalous hall regime. We use a scanning superconducting quantum interference device (SQUID) microscope with micrometer scale spatial resolution to image the magnetic fields above current biased devices. Using these images, we reconstruct the current density, allowing us to visualize where current flows in the devices. We also use top and back gates to study how magnetization is affected by electrostatic gating. By performing these measurements as a function of current bias, gate voltage and magnetization direction, we construct a comprehensive picture of electronic transport in our devices.

*Work at Cornell University was primarily supported by the Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering, under Award DE-SC0015947.

Sample synthesis at Penn State was supported by the Penn State 2DCC-MIP under NSF Grant No. DMR-1539916.

Presenters

  • George Ferguson

    • Cornell University

Authors

  • George Ferguson

    • Cornell University
  • Run Xiao

    • Pennsylvania State University
    • Physics, Pennsylvania State University
  • David Low

    • Cornell University
  • Ling-Jie Zhou

    • Pennsylvania State University
  • Anthony R. Richardella

    • Pennsylvania State University
    • Physics, The Pennsylvania State University
    • The Pennsylvania State University
    • Physics, Pennsylvania State University
  • Cui-Zu Chang

    • Pennsylvania State University
    • Department of Physics, The Pennsylvania State University
    • Department of Physics, Pennsylvania State University
    • The Pennsylvania State University
  • Nitin Samarth

    • Pennsylvania State University
    • Department of Physics, The Pennsylvania State University
    • Physics, The Pennsylvania State University
    • Physics, Pennsylvania State University
    • The Pennsylvania State University
  • Katja Nowack

    • Physics, Cornell University
    • Cornell University