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arXiv · 1105.1252

Z_2 Topological Insulators in Ultracold Atomic Gases

B. Béri·N. R. Cooper
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Abstract

We describe how optical dressing can be used to generate bandstructures for ultracold atoms with non-trivial Z_2 topological order. Time reversal symmetry is preserved by simple conditions on the optical fields. We first show how to construct optical lattices that give rise to Z_2 topological insulators in two dimensions. We then describe a general method for the construction of three-dimensional Z_2 topological insulators. A central feature of our approach is a new way to understand Z_2 topological insulators starting from the nearly-free electron limit.

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B. Béri, N. R. Cooper. 2011-12-20. Z_2 Topological Insulators in Ultracold Atomic Gases. https://doi.org/10.1103/physrevlett.107.145301

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