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arXiv · 0904.0690

Topological insulators in three dimensions from spontaneous symmetry breaking

Yi Zhang·Ying Ran·Ashvin Vishwanath
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Abstract

We study three dimensional systems where strong repulsion leads to an insulating state via spontaneously generated spin-orbit interactions. We discuss a microscopic model where the resulting state is topological. Such topological `Mott' insulators differ from their band insulator counterparts in that they possess an additional order parameter, a rotation matrix, that describes the spontaneous breaking of spin-rotation symmetry. We show that line defects of this order are associated with protected one dimensional modes in the {\em strong} topological Mott insulator, which provides a bulk characterization of this phase.

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Yi Zhang, Ying Ran, Ashvin Vishwanath. 2009-04-20. Topological insulators in three dimensions from spontaneous symmetry breaking. https://doi.org/10.1103/physrevb.79.245331

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