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arXiv · 1810.08319

Power and Efficiency of a Thermal Engine with a Coherent Bath

Thomas Guff·Shakib Daryanoosh·Ben Q. Baragiola·Alexei Gilchrist
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Abstract

We consider a quantum engine driven by repeated weak interactions with a heat bath of identical three-level atoms. This model was first introduced by Scully et al. [Science, 2003], who showed that coherence between the energy-degenerate ground states serves as a thermodynamic resource that allows operation of a thermal cycle with a coherence-dependent thermalisation temperature. We consider a similar engine out of the quasistatic limit and find that the ground-state coherence also determines the rate of thermalisation, therefore increasing the output power and the engine efficiency only when the thermalisation temperature is reduced; revealing a more nuanced perspective of coherence as a resource. This allows us to optimise the output power by adjusting the coherence and relative stroke durations.

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Thomas Guff, Shakib Daryanoosh, Ben Q. Baragiola, Alexei Gilchrist. 2019-09-24. Power and Efficiency of a Thermal Engine with a Coherent Bath. https://doi.org/10.1103/physreve.100.032129

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