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arXiv · 1209.6249

Topological phase transitions in bulk

Stanislav Chadov·Janos Kiss·Jürgen Kübler·Claudia Felser
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Abstract

We consider the analogy between the topological phase transition which occurs as a function of spatial coordinate on a surface of a non-trivial insulator, and the one which occurs in the bulk due to the change of internal parameters (such as crystal field and spin-orbit coupling). In both cases the system exhibits a Dirac cone, which is the universal manifestation of topological phase transition, independently on the type of driving parameters. In particular, this leads to a simple way of determining the topological class based solely on the bulk information even for the systems with translational symmetry broken by atomic disorder or by strong electron correlations. Here we demonstrate this on example of the zinc-blende related semiconductors by means of the {\it ab-initio} fully-relativistic band structure calculations involving the coherent potential approximation (CPA) technique.

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Stanislav Chadov, Janos Kiss, Jürgen Kübler, Claudia Felser. 2012-09-27. Topological phase transitions in bulk. https://doi.org/10.1002/pssr.201206395

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