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arXiv · 1011.0565

Spin connection and boundary states in a topological insulator

V. Parente·P. Lucignano·P. Vitale·A. Tagliacozzo·F. Guinea
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Abstract

We study the surface resistivity of a three-dimensional topological insulator when the boundaries exhibit a non trivial curvature. We obtain an analytical solution for a spherical topological insulator, and we show that a non trivial quantum spin connection emerges from the three dimensional band structure. We analyze the effect of the spin connection on the scattering by a bump on a flat surface. Quantum effects induced by the geometry lead to resonances when the electron wavelength is comparable to the size of the bump.

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V. Parente, P. Lucignano, P. Vitale, A. Tagliacozzo, F. Guinea. 2010-11-02. Spin connection and boundary states in a topological insulator. https://doi.org/10.1103/physrevb.83.075424

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