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arXiv · 1411.1388

Power enhancement of heat engines via correlated thermalization in multilevel systems

David Gelbwaser-Klimovsky·Wolfgang Niedenzu·Paul Brumer·Gershon Kurizki
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Abstract

We analyze a heat machine based on a periodically-driven quantum system permanently coupled to hot and cold baths. It is shown that the maximal power output of a degenerate $V$-type three-level heat engine is that generated by two independent two-level systems. For $N$ levels, this maximal enhancement is $(N-1)$-fold. Hence, level degeneracy is a thermodynamic resource that may effectively boost the power output. The efficiency, however, is not affected. We find that coherence is not an essential asset in multilevel-based heat machines. The existence of multiple thermalization pathways sharing a common ground state suffices for power enhancement.

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David Gelbwaser-Klimovsky, Wolfgang Niedenzu, Paul Brumer, Gershon Kurizki. 2014-11-05. Power enhancement of heat engines via correlated thermalization in multilevel systems. https://doi.org/10.1038/srep14413

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