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arXiv · 2506.22121

Macroscopic theory of multipartite correlations in permutation-invariant open quantum systems

Krzysztof Ptaszynski·Maciej Chudak·Massimiliano Esposito
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Abstract

Information-theoretic quantities have received significant attention as system-independent measures of correlations in many-body quantum systems, e.g., as universal order parameters of synchronization. In this work, we present a method to determine the macroscopic behavior of the steady-state multipartite mutual information between $N$ interacting units undergoing Markovian evolution that is invariant under unit permutations. Using this approach, we extend a conclusion previously drawn for classical systems that the extensive scaling of mutual information is either not possible for systems relaxing to fixed points of the mean-field dynamics or such scaling is not robust to perturbations of system dynamics. In contrast, robust extensive scaling occurs for system relaxing to time-dependent attractors, e.g., limit cycles. We illustrate the applicability of our method on the driven-dissipative Lipkin-Meshkov-Glick model.

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Krzysztof Ptaszynski, Maciej Chudak, Massimiliano Esposito. 2025-06-27. Macroscopic theory of multipartite correlations in permutation-invariant open quantum systems. https://doi.org/10.1103/zwfx-m4nq

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