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arXiv · 2508.06018

Magic Entropy in Hybrid Spin-Boson Systems

Samuel Crew·Ying-Lin Li·Heng-Hsi Li·Po-Yao Chang
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Abstract

We introduce entropic measures to quantify non-classical resource in hybrid spin-boson systems. We discuss the stabilizer R\'enyi entropy in the framework of phase space quantisation and define an analogous hybrid magic entropy and a mutual magic entropy that capture the distribution of quantum magic across spin and bosonic subsystems. We use these entropic measures to demonstrate two key phenomena: the detection of the superradiant phase transition in the Dicke model and the dynamics of magic in the Jaynes-Cummings model following a quench. We develop a Monte Carlo numerical scheme to enable practical computation in many-body examples.

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Samuel Crew, Ying-Lin Li, Heng-Hsi Li, Po-Yao Chang. 2025-08-08. Magic Entropy in Hybrid Spin-Boson Systems. https://arxiv.org/abs/2508.06018

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