Probing Magnetically Doped Topological Insulators with Capacitance Measurements

ORAL

Abstract

Topological effects in zero magnetic field are currently of high interest. Among these, the quantum anomalous Hall effect features a Hall resistance quantized to ±h/e2 at zero field, which can be realized in magnetically doped topological insulators. The net transport current in the quantum anomalous Hall effect is thought to be carried by dissipationless edge states, with the bulk dominated by localized non-conducting states. Recent works investigating the electrostatic potential and local current density in the quantum anomalous Hall effect have suggested that transport current flows primarily in the bulk at some carrier densities. Going beyond the traditional transport measurements, here we report capacitance measurements of a Cr-doped (Bi,Sb)2Te3 quantum anomalous Hall insulator to probe the conductive behavior of the entire sample surface.

*Measurements at Purdue were supported by the US Department of Energy Basic Energy Sciences Program under the award DE-SC0006671. Sample growth supported by JSPS KAKENHI Grant No. 23H01861 and by the RIKEN TRIP initiative (Many-body Electron Systems)

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Presenters

  • Adam Bozzone

    • Purdue University

Authors

  • Adam Bozzone

    • Purdue University

  • Ryutaro Yoshimi

    • Department of Advanced Materials Science, The University of Tokyo

  • Minoru Kawamura

    • RIKEN Center for Emergent Matter Science (CEMS)

  • Atsushi Tsukazaki

    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), The University of Tokyo
    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), University of Tokyo

  • Masashi Kawasaki

    • RIKEN Center for Emergent Matter Science (CEMS), Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), The University of Tokyo
    • RIKEN Center for Emergent Matter Science (CEMS), Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), University of Tokyo

  • Yoshinori Tokura

    • RIKEN Center for Emergent Matter Science (CEMS), Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), The University of Tokyo
    • Univ of Tokyo
    • The University of Tokyo, RIKEN Center for Emergent Matter Science (CEMS), Tokyo college, The University of Tokyo
    • RIKEN Center for Emergent Matter Science (CEMS); Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), Univ. of Tokyo; Tokyo College, Univ. of Tokyo
    • RIKEN Center for Emergent Matter Science (CEMS), Department of Applied Physics, Quantum-Phase Electronics Center (QPEC) and Tokyo College, University of Tokyo

  • Gabor A Csathy

    • Purdue University