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arXiv · 2110.15151

Haar averaged moments of correlation functions and OTOCs in Floquet systems

Ewan McCulloch
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Abstract

Scrambling and thermalisation are topics of intense study in both condensed matter and high energy physics. Random unitary dynamics form a simple testing-ground for our theoretical understanding of these processes. In this work, we derive exact expressions for the large $q$ limiting behaviour of a selection of $n$-point correlation functions, out-of-time-ordered correlators (OTOCs), and their moments. In the process we find a general principle that breaks OTOCs into small and easy to calculate pieces, and which can likely be deployed in a more general context.

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Ewan McCulloch. 2021-10-28. Haar averaged moments of correlation functions and OTOCs in Floquet systems. https://arxiv.org/abs/2110.15151

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