Proposal for many-body quantum chaos detection with single-site measurements

Isaías Vallejo-Fabila; Adway Kumar Das; Sayan Choudhury; Lea F. Santos

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arXiv · 2505.05572

Proposal for many-body quantum chaos detection with single-site measurements

Isaías Vallejo-Fabila·Adway Kumar Das·Sayan Choudhury·Lea F. Santos

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Abstract

We demonstrate that the long-time dynamics of an observable associated with a single lattice site is sufficient to determine whether a many-body quantum system exhibits level statistics characteristic of random matrix theory, a widely used diagnostic of quantum chaos. In particular, we focus on the partial survival probability and spin autocorrelation function at a single site, both evolved under a disordered spin-1/2 chain, which is a setup realizable in current experimental platforms. Given the precision and timescales currently achievable, our results indicate that the detection of many-body quantum chaos is feasible, but constrained to small system sizes.

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Isaías Vallejo-Fabila, Adway Kumar Das, Sayan Choudhury, Lea F. Santos. 2025-05-08. Proposal for many-body quantum chaos detection with single-site measurements. https://arxiv.org/abs/2505.05572

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