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arXiv · 1004.2777

Edge Dynamics in a Quantum Spin Hall State: Effects from Rashba Spin-Orbit Interaction

Anders Ström·Henrik Johannesson·G. I. Japaridze
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Abstract

We analyze the dynamics of the helical edge modes of a quantum spin Hall state in the presence of a spatially non-uniform Rashba spin-orbit (SO) interaction. A randomly fluctuating Rashba SO coupling is found to open a scattering channel which causes localization of the edge modes for a weakly screened electron-electron (e-e) interaction. A periodic modulation of the SO coupling, with a wave number commensurate with the Fermi momentum, makes the edge insulating already at intermediate strengths of the e-e interaction. We discuss implications for experiments on edge state transport in a HgTe quantum well.

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Anders Ström, Henrik Johannesson, G. I. Japaridze. 2010-06-29. Edge Dynamics in a Quantum Spin Hall State: Effects from Rashba Spin-Orbit Interaction. https://doi.org/10.1103/physrevlett.104.256804

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