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arXiv · 2604.02484

Hybrid quantum-classical dynamics with stationary thermal states

Adrián A. Budini
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Abstract

Quantum and classical systems can consistently be coupled via non-unitary time-irreversible mechanisms. In this paper we characterize which kind of corresponding dynamics converge in the stationary regime to a thermal hybrid state, that is, a density matrix that maximizes the hybrid arrangement entropy under the constraints of a canonical ensemble. Introducing a detailed balance condition, it is found that a specific subclass of hybrid Lindblad equations fulfill the demanded requirement. The main theoretical results are exemplified through a set of specific examples that in addition lighten how the thermal state of each subsystem in isolation is affected by their mutual coupling. In particular, a Gaussian thermal state could become a bimodal distribution when increasing the interaction strength of a classical subsystem with a quantum two-level subsystem.

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Adrián A. Budini. 2026-04-02. Hybrid quantum-classical dynamics with stationary thermal states. https://doi.org/10.1103/3vh7-cjcs

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