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arXiv · 1508.06519

On the operation of machines powered by quantum non-thermal baths

Wolfgang Niedenzu·David Gelbwaser-Klimovsky·Abraham G. Kofman·Gershon Kurizki
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Abstract

Diverse models of engines energised by quantum-coherent, hence non-thermal, baths allow the engine efficiency to transgress the standard thermodynamic Carnot bound. These transgressions call for an elucidation of the underlying mechanisms. Here we show that non-thermal baths may impart not only heat, but also mechanical work to a machine. The Carnot bound is inapplicable to such a hybrid machine. Intriguingly, it may exhibit dual action, concurrently as engine and refrigerator, with up to 100% efficiency. We conclude that even though a machine powered by a quantum bath may exhibit an unconventional performance, it still abides by the traditional principles of thermodynamics.

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Wolfgang Niedenzu, David Gelbwaser-Klimovsky, Abraham G. Kofman, Gershon Kurizki. 2016-07-11. On the operation of machines powered by quantum non-thermal baths. https://doi.org/10.1088/1367-2630%2F18%2F8%2F083012

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