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arXiv · 1709.04830

Robust Helical Edge Transport in Quantum Spin Hall Quantum Wells

Rafal Skolasinski·Dmitry I. Pikulin·Jason Alicea·Michael Wimmer
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Abstract

We show that burying of the Dirac point in semiconductor-based quantum-spin-Hall systems can generate unexpected robustness of edge states to magnetic fields. A detailed ${\bf k\cdot p}$ band-structure analysis reveals that InAs/GaSb and HgTe/CdTe quantum wells exhibit such buried Dirac points. By simulating transport in a disordered system described within an effective model, we further demonstrate that buried Dirac points yield nearly quantized edge conduction out to large magnetic fields, consistent with recent experiments.

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Rafal Skolasinski, Dmitry I. Pikulin, Jason Alicea, Michael Wimmer. 2017-09-14. Robust Helical Edge Transport in Quantum Spin Hall Quantum Wells. https://doi.org/10.1103/physrevb.98.201404

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