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arXiv · 1010.0503

Z2 invariant protected bound states in topological insulators

Wen-Yu Shan·Jie Lu·Hai-Zhou Lu·Shun-Qing Shen
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Abstract

We present an exact solution of a modifed Dirac equation for topological insulator in the presence of a hole or vacancy to demonstrate that vacancies may induce bound states in the band gap of topological insulators. They arise due to the Z_2 classification of time-reversal invariant insulators, thus are also topologically-protected like the edge states in the quantum spin Hall effect and the surface states in three-dimensional topological insulators. Coexistence of the in-gap bound states and the edge or surface states in topological insulators suggests that imperfections may affect transport properties of topological insulators via additional bound states near the system boundary.

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Wen-Yu Shan, Jie Lu, Hai-Zhou Lu, Shun-Qing Shen. 2010-10-08. Z2 invariant protected bound states in topological insulators. https://doi.org/10.1103/physrevb.84.035307

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