Bulk-boundary correspondence for interacting Floquet systems in two dimensions

Carolyn Zhang; Michael Levin

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arXiv · 2209.03975

Bulk-boundary correspondence for interacting Floquet systems in two dimensions

Carolyn Zhang·Michael Levin

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Abstract

We present a method for deriving bulk and edge invariants for interacting, many-body localized Floquet systems in two spatial dimensions. This method is based on a general mathematical object which we call a flow. As an application of our method, we derive bulk invariants for Floquet systems without symmetry, as well as for systems with $U(1)$ symmetry. We also derive new formulations of previously known single-particle and many-body invariants. For bosonic systems without symmetry, our invariant gives a bulk counterpart of the rational-valued GNVW index $\frac{p}{q}$ quantifying transport of quantum information along the edge.

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Carolyn Zhang, Michael Levin. 2022-09-08. Bulk-boundary correspondence for interacting Floquet systems in two dimensions. https://arxiv.org/abs/2209.03975

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