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arXiv · 1406.1490

Effective Theory of Floquet Topological Transitions

Arijit Kundu·H. A. Fertig·Babak Seradjeh
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Abstract

We develop a theory of topological transitions in a Floquet topological insulator, using graphene irradiated by circularly polarized light as a concrete realization. We demonstrate that a hallmark signature of such transitions in a static system, i.e. metallic bulk transport with conductivity of order $e^2/h$, is substantially suppressed at some Floquet topological transitions in the clean system. We determine the conditions for this suppression analytically and confirm our results in numerical simulations. Remarkably, introducing disorder dramatically enhances this transport by several orders of magnitude.

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Arijit Kundu, H. A. Fertig, Babak Seradjeh. 2014-06-05. Effective Theory of Floquet Topological Transitions. https://doi.org/10.1103/physrevlett.113.236803

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