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arXiv · 2405.16974

Inherent quantum resources in stationary spin chains

Marcin Płodzień·Jan Chwedeńczuk·Maciej Lewenstein
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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 non-classical 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 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.

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Marcin Płodzień, Jan Chwedeńczuk, Maciej Lewenstein. 2024-05-27. Inherent quantum resources in stationary spin chains. https://doi.org/10.1103/physreva.111.012417

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