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arXiv · 2506.17547

Edge of Many-Body Quantum Chaos in Quantum Reservoir Computing

Kaito Kobayashi·Yukitoshi Motome
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Abstract

Reservoir computing (RC) is a machine learning paradigm that harnesses dynamical systems as computational resources. In its quantum extension -- quantum reservoir computing (QRC) -- these principles are applied to quantum systems, whose rich dynamics broadens the landscape of information processing. In classical RC, optimal performance is typically achieved at the ``edge of chaos," the boundary between order and chaos. Here, we identify its quantum many-body counterpart using the QRC implemented on the celebrated Sachdev-Ye-Kitaev model. Our analysis reveals substantial performance enhancements near two distinct characteristic ``edges": a temporal boundary defined by the Thouless time, beyond which system dynamics is described by random matrix theory, and a parametric boundary governing the transition from integrable to chaotic regimes. These findings establish the ``edge of many-body quantum chaos" as a design guideline for QRC.

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Kaito Kobayashi, Yukitoshi Motome. 2025-06-21. Edge of Many-Body Quantum Chaos in Quantum Reservoir Computing. https://doi.org/10.1103/j2qj-vwcl

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