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arXiv · 2003.04849

Evidence for unbounded growth of the number entropy in many-body localized phases

Maximilian Kiefer-Emmanouilidis·Razmik Unanyan·Michael Fleischhauer·Jesko Sirker
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Abstract

We investigate the number entropy $S_N$---which characterizes particle-number fluctuations between subsystems---following a quench in one-dimensional interacting many-body systems with potential disorder. We find evidence that in the regime which is expected to show many-body localization (MBL) and where the entanglement entropy grows as $S\sim \ln t$ as function of time $t$, the number entropy grows as $S_N\sim\ln\ln t$, indicating continuing particle transport at a very slow rate. We demonstrate that this growth is consistent with a relation between entanglement and number entropy recently established for non-interacting systems.

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Maximilian Kiefer-Emmanouilidis, Razmik Unanyan, Michael Fleischhauer, Jesko Sirker. 2020-03-10. Evidence for unbounded growth of the number entropy in many-body localized phases. https://doi.org/10.1103/physrevlett.124.243601

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