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arXiv · 1907.12228

Hierarchy of many-body invariants and quantized magnetization in anomalous Floquet insulators

Frederik Nathan·Dmitry A. Abanin·Netanel H. Lindner·Erez Berg·Mark S. Rudner
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Abstract

We uncover a new family of few-body topological phases in periodically driven fermionic systems in two dimensions. These phases, which we term correlation-induced anomalous Floquet insulators (CIAFIs), are characterized by quantized contributions to the bulk magnetization from multi-particle correlations, and are classified by a family of integer-valued topological invariants. The CIAFI phases do not require many-body localization, but arise in the generic situation of k-particle localization, where the system is localized (due to disorder) for any finite number of particles up to a maximum number, k. We moreover show that, when fully many-body localized, periodically driven systems of interacting fermions in two dimensions are characterized by a quantized magnetization in the bulk, thus confirming the quantization of magnetization of the anomalous Floquet insulator. We demonstrate our results with numerical simulations.

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Frederik Nathan, Dmitry A. Abanin, Netanel H. Lindner, Erez Berg, Mark S. Rudner. 2021-02-22. Hierarchy of many-body invariants and quantized magnetization in anomalous Floquet insulators. https://doi.org/10.21468/scipostphys.10.6.128

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