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Power enhancement of heat engines via correlated thermalization in a three-level "working fluid"
David Gelbwaser-Klimovsky1,2, Wolfgang Niedenzu2, Paul Brumer3
1Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.
Abstract:
We explore means of maximizing the power output of a heat engine based on a periodically-driven quantum system that is constantly coupled to hot and cold baths. It is shown that the maximal power output of such a heat engine whose "working fluid" is a degenerate V-type three-level system is that generated by two independent two-level systems. Hence, level degeneracy is a thermodynamic resource that may effectively double the power output. The efficiency, however, is not affected. We find that coherence is not an essential asset in such multilevel-based heat engines. The existence of two thermalization pathways sharing a common ground state suffices for power enhancement.
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