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arXiv · 2011.02848

Almost complete revivals in quantum many-body systems

Igor Ermakov·Boris V. Fine
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Abstract

Revivals of initial non-equilibrium states is an ever-present concern for the theory of dynamic thermalization in many-body quantum systems. Here we consider a nonintegrable lattice of interacting spins 1/2 and show how to construct a quantum state such that a given spin 1/2 is maximally polarized initially and then exhibits an almost complete recovery of the initial polarization at a predetermined moment of time. An experimental observation of such revivals may be utilized to benchmark quantum simulators with a measurement of only one local observable. We further propose to utilize these revivals for a delayed disclosure of a secret.

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Igor Ermakov, Boris V. Fine. 2020-11-05. Almost complete revivals in quantum many-body systems. https://doi.org/10.1103/physreva.104.l050202

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