Optimal linear cyclic quantum heat engines cannot benefit from strong
coupling
- URL: http://arxiv.org/abs/2206.11453v2
- Date: Mon, 4 Jul 2022 06:13:38 GMT
- Title: Optimal linear cyclic quantum heat engines cannot benefit from strong
coupling
- Authors: Junjie Liu and Kenneth A. Jung
- Abstract summary: We show that strong system-bath coupling is detrimental to quantum heat engines (QHEs) operated under a small temperature difference.
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.
- Score: 6.211723927647019
- License: http://creativecommons.org/licenses/by/4.0/
- 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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