Robust helical edge transport in quantum spin Hall quantum wells
Abstract
We show that edge-state transport in semiconductor-based quantum spin Hall systems is unexpectedly robust to magnetic fields. The origin for this robustness lies in an intrinsic suppression of the edge-state g-factor and the fact that the edge-state Dirac point is typically hidden in the valence band. A detailed k⋅p band-structure analysis reveals that both InAs/GaSb and HgTe/CdTe quantum wells exhibit such buried Dirac points for a wide range of well thicknesses. By simulating transport in a disordered system described within an effective model, we demonstrate that edge-state transport remains nearly quantized up to large magnetic fields, consistent with recent experiments.
Additional Information
© 2018 American Physical Society. Received 14 September 2017; published 14 November 2018. We acknowledge useful discussions with L. Molenkamp, A. R. Akhmerov, and T. Hyart. R.S. and M.W. were supported by the Dutch national science organization NWO. D.I.P. acknowledges support by Microsoft Corporation Station Q. J.A. gratefully acknowledges support from the National Science Foundation through Grant No. DMR-1723367; the Army Research Office under Grant Award No. W911NF-17-1-0323; the Caltech Institute for Quantum Information and Matter, an NSF Physics Frontiers Center with support of the Gordon and Betty Moore Foundation through Grant No. GBMF1250; and the Walter Burke Institute for Theoretical Physics at Caltech.Attached Files
Published - PhysRevB.98.201404.pdf
Submitted - 1709.04830.pdf
Supplemental Material - supplementary.pdf
Files
Additional details
- Eprint ID
- 82083
- Resolver ID
- CaltechAUTHORS:20171004-145628173
- Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)
- Microsoft Corporation Station Q
- NSF
- DMR-1723367
- Army Research Office
- W911NF-17-1-0323
- Institute for Quantum Information and Matter (IQIM)
- Gordon and Betty Moore Foundation
- GBMF1250
- Walter Burke Institute for Theoretical Physics, Caltech
- Created
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2017-10-05Created from EPrint's datestamp field
- Updated
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2021-11-15Created from EPrint's last_modified field
- Caltech groups
- Institute for Quantum Information and Matter, Walter Burke Institute for Theoretical Physics