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arXiv · 2510.27376

Fate and origin of the quantum Otto heat engine based on the dissipative Dicke-Hubbard model

He-Guang Xu·Shujie Cheng
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Abstract

The Dicke-Hubbard model, describing an ensemble of interacting atoms in a cavity, provides a rich platform for exploring collective quantum phenomena. However, its potential for quantum thermodynamic applications remains largely uncharted. Here, we study a quantum Otto heat engine whose working substance is a system governed by the Dicke-Hubbard Hamiltonian. Through the research on steady-state superradiance phase transitions, it is demonstrated that the steady-state synergistic mechanism under high and low temperature environments is the reason for the emergence of high-performance heat engines. By analyzing the influences of atom-light coupling strength, inter-cavity hopping strength and atom number on the working modes of quantum Otto cycle, it is clarified that the effective working regions of each working mode. This work has established a close connection between superradiance phase transition and the quantum thermodynamic applications. It not only deepens our understanding of the energy conversion mechanism in non-equilibrium quantum thermodynamics but also lays a theoretical foundation for the future experimental design of high-performance quantum Otto heat engines.

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He-Guang Xu, Shujie Cheng. 2025-10-31. Fate and origin of the quantum Otto heat engine based on the dissipative Dicke-Hubbard model. https://arxiv.org/abs/2510.27376

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