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arXiv · 1006.4496

Helical Luttinger liquid in topological insulator nanowires

R. Egger·A. Zazunov·A. Levy Yeyati
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Abstract

We derive and analyze the effective low-energy theory for interacting electrons in a cylindrical nanowire made of a strong topological insulator. Three different approaches provide a consistent picture for the band structure, where surface states forming inside the bulk gap correspond to one-dimensional bands indexed by total angular momentum. When a half-integer magnetic flux pierces the nanowire, we find a strongly correlated helical Luttinger liquid topologically protected against weak disorder. We describe how transport experiments can detect this state.

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R. Egger, A. Zazunov, A. Levy Yeyati. 2010-06-23. Helical Luttinger liquid in topological insulator nanowires. https://doi.org/10.1103/physrevlett.105.136403

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