Bulk dissipation in the quantum anomalous Hall effect
Abstract
Even at the lowest accessible temperatures, measurements of the quantum anomalous Hall (QAH) effect have indicated the presence of parasitic dissipative conduction channels. There is no consensus whether parasitic conduction is related to processes in the bulk or along the edges. Here, we approach this problem by comparing transport measurements of Hall bar and Corbino geometry devices fabricated from Cr-doped (BiSb)2Te3. We identify bulk conduction as the dominant source of dissipation at all values of temperature and in-plane electric field. Furthermore, we observe identical breakdown phenomenology in both geometries, indicating that breakdown of the QAH phase is a bulk process. The methodology developed in this study could be used to identify dissipative conduction mechanisms in new QAH materials, ultimately guiding material development toward realization of the QAH effect at higher temperatures.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 01, 2021
- Source ID
- 10.1063/5.0056796
Entities
People
- David Goldhaber-Gordon
- E. J. Fox
- Ilan T. Rosen
- Kang L. Wang
- Lei Pan
- Linsey K. Rodenbach
- M. A. Kastner
- Peng Zhang
Organizations
- Army Research Office
- Gordon and Betty Moore Foundation
- Massachusetts Institute of Technology
- National Science Foundation
- SLAC National Accelerator Laboratory
- Stanford University
- United States Department of Energy
- University of California, Los Angeles