Edge dynamics in a quantum spin Hall state: effects from Rashba spin-orbit interaction.
نویسندگان
چکیده
We analyze the dynamics of the helical edge modes of a quantum spin Hall state in the presence of a spatially nonuniform 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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عنوان ژورنال:
- Physical review letters
دوره 104 25 شماره
صفحات -
تاریخ انتشار 2010