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arXiv · 2206.11453

Optimal linear cyclic quantum heat engines cannot benefit from strong coupling

Junjie Liu·Kenneth A. Jung
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Abstract

Uncovering whether strong system-bath coupling can be an advantageous operation resource for energy conversion can facilitate the development of efficient quantum heat engines (QHEs). Yet, a consensus on this ongoing debate is still lacking owing to challenges arising from treating strong couplings. Here we conclude the debate for optimal linear cyclic QHEs operated under a small temperature difference by revealing the detrimental role of strong system-bath coupling in their optimal operations. We analytically demonstrate that both the efficiency at maximum power and maximum efficiency of strong-coupling linear cyclic QHEs are upper bounded by their weak-coupling counterparts and, particularly, experience a quadratic suppression relative to the Carnot limit under strong time-reversal symmetry breaking.

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Junjie Liu, Kenneth A. Jung. 2022-06-23. Optimal linear cyclic quantum heat engines cannot benefit from strong coupling. https://doi.org/10.1103/physreve.106.l022105

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