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arXiv · 1209.1190

Minimal universal quantum heat machine

David Gelbwaser-Klimovsky·Robert Alicki·Gershon Kurizki
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Abstract

In traditional thermodynamics the Carnot cycle yields the ideal performance bound of heat engines and refrigerators. We propose and analyze a minimal model of a heat machine that can play a similar role in quantum regimes. The minimal model consists of a single two-level system with periodically modulated energy splitting that is permanently, weakly, coupled to two spectrally-separated heat baths at different temperatures. The equation of motion allows to compute the stationary power and heat currents in the machine consistently with the second-law of thermodynamics. This dual-purpose machine can act as either an engine or a refrigerator (heat pump) depending on the modulation rate. In both modes of operation the maximal Carnot efficiency is reached at zero power. We study the conditions for finite-time optimal performance for several variants of the model. Possible realizations of the model are discussed.

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David Gelbwaser-Klimovsky, Robert Alicki, Gershon Kurizki. 2013-01-29. Minimal universal quantum heat machine. https://doi.org/10.1103/physreve.87.012140

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