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arXiv · 2003.12664

Two-level quantum Otto heat engine operating with unit efficiency far from the quasi-static regime under a squeezed reservoir

Rogério J. de Assis·J. S. Sales·Udson C. Mendes·Norton G. de Almeida
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Abstract

Recent theoretical and experimental studies in quantum heat engines show that, in the quasi-static regime, it is possible to have higher efficiency than the limit imposed by Carnot, provided that engineered reservoirs are used. The quasi-static regime, however, is a strong limitation to the operation of heat engines, since infinitely long time is required to complete a cycle. In this paper we propose a two-level model as the working substance to perform a quantum Otto heat engine surrounded by a cold thermal reservoir and a squeezed hot thermal reservoir. Taking advantage of this model we show a striking achievement, that is to attain unity efficiency even at non null power.

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Rogério J. de Assis, J. S. Sales, Udson C. Mendes, Norton G. de Almeida. 2020-03-27. Two-level quantum Otto heat engine operating with unit efficiency far from the quasi-static regime under a squeezed reservoir. https://doi.org/10.1088/1361-6455/abcfd9

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