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arXiv · 1906.00292

Enhancement of efficiency in the Dicke model quantum heat engine

M. Aparicio Alcalde·E. Arias·N. F. Svaiter
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Abstract

We analyze a quantum heat engine described by the full Dicke model. The system exhibit quantum phase transitions under certain conditions. We consider the system performing a Stirling thermodynamic cycle. We obtain an enhancement of efficiency when during the cycle the coupling parameter cross a critical value. We analyze the effect of unbalance between rotating and counter-rotating terms in the model. The maximum efficiency is obtained when the contributions of the counter-rotating and rotating terms are equal. The relation between ground state degeneracy, related to the quantum phase transition, and maximum efficiency is investigated.

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M. Aparicio Alcalde, E. Arias, N. F. Svaiter. 2019-06-01. Enhancement of efficiency in the Dicke model quantum heat engine. https://arxiv.org/abs/1906.00292

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