Characterization of 3d topological insulators by 2d invariants

Rahul Roy

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arXiv · 1004.3507

Characterization of 3d topological insulators by 2d invariants

Rahul Roy

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Abstract

The prediction of non-trivial topological phases in Bloch insulators in three dimensions has recently been experimentally verified. Here, I provide a picture for obtaining the $Z_{2}$ invariants for a three dimensional topological insulator by deforming suitable 2d planes in momentum space and by using a formula for the 2d $Z_{2}$ invariant based on the Chern number. The physical interpretation of this formula is also clarified through the connection between this formulation of the $Z_{2}$ invariant and the quantization of spin Hall conductance in two dimensions.

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Rahul Roy. 2010-04-20. Characterization of 3d topological insulators by 2d invariants. https://arxiv.org/abs/1004.3507

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