arXiv:2405.16974 · Physical Review A

Inherent quantum resources in stationary spin chains

Marcin Płodzień, Jan Chwedeńczuk, Maciej Lewenstein

Published Jan 9, 2025• 5 citations

Abstract

The standard way to generate many-body quantum correlations is via a dynamical protocol: an initial product state is transformed by interactions that generate nonclassical correlations at later times. Here, we show that many-body Bell correlations are inherently present in the eigenstates of a variety of spin-1/2 chains. In particular, we show that the eigenstates and thermal states of the collective Lipkin-Meshkov-Glick model possess many-body Bell correlations. We demonstrate that the Bell correlations present in the eigenstates of the Lipkin-Meshkov-Glick model can take on quantized values that change discontinuously with variations in the total magnetization. Finally, we show that these many-body Bell correlations persist even in the presence of both diagonal and off-diagonal disorder.

DOI: 10.1103/physreva.111.012417

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