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arXiv · 1708.01173

Topological boundary invariants for Floquet systems and quantum walks

Christian Sadel·Hermann Schulz-Baldes
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Abstract

A Floquet systems is a periodically driven quantum system. It can be described by a Floquet operator. If this unitary operator has a gap in the spectrum, then one can define associated topological bulk invariants which can either only depend on the bands of the Floquet operator or also on the time as a variable. It is shown how a K-theoretic result combined with the bulk-boundary correspondence leads to edge invariants for the half-space Floquet operators. These results also apply to topological quantum walks.

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Christian Sadel, Hermann Schulz-Baldes. 2017-09-26. Topological boundary invariants for Floquet systems and quantum walks. https://doi.org/10.1007/s11040-017-9253-1

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