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arXiv · 1403.1082

Random Rashba spin-orbit coupling at the quantum spin Hall edge

Florian Geissler·Francois Crépin·Björn Trauzettel
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Abstract

We study a one-dimensional helical system with random Rashba spin-orbit coupling. Using renor- malization group methods, we derive a consistent set of flow equations governing the important con- trol parameters of the backscattering process. Thereby, we prove the existence of disorder-induced two-particle backscattering that can even be non-local in space. This analysis allows us to derive the scaling form of the conductance at low temperatures. We find that two-particle backscattering due to random spin-orbit coupling differs from the one off a single Rashba impurity by both the scaling of the conductance with the temperature and the relevance of the backscattering operators.

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Florian Geissler, Francois Crépin, Björn Trauzettel. 2014-07-09. Random Rashba spin-orbit coupling at the quantum spin Hall edge. https://doi.org/10.1103/physrevb.89.235136

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