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arXiv · 2009.03186

Flow Equations for Disordered Floquet Systems

S. J. Thomson·D. Magano·M. Schiró
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Abstract

In this work, we present a new approach to disordered, periodically driven (Floquet) quantum many-body systems based on flow equations. Specifically, we introduce a continuous unitary flow of Floquet operators in an extended Hilbert space, whose fixed point is both diagonal and time-independent, allowing us to directly obtain the Floquet modes. We first apply this method to a periodically driven Anderson insulator, for which it is exact, and then extend it to driven many-body localized systems within a truncated flow equation ansatz. In particular we compute the emergent Floquet local integrals of motion that characterise a periodically driven many-body localized phase. We demonstrate that the method remains well-controlled in the weakly-interacting regime, and allows us to access larger system sizes than accessible by numerically exact methods, paving the way for studies of two-dimensional driven many-body systems.

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BibTeXRIS

S. J. Thomson, D. Magano, M. Schiró. 2020-09-07. Flow Equations for Disordered Floquet Systems. https://doi.org/10.21468/scipostphys.11.2.028

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