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arXiv · 1506.07875

The extraction of work from quantum coherence

Kamil Korzekwa·Matteo Lostaglio·Jonathan Oppenheim·David Jennings
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Abstract

The interplay between quantum-mechanical properties, such as coherence, and classical notions, such as energy, is a subtle topic at the forefront of quantum thermodynamics. The traditional Carnot argument limits the conversion of heat to work; here we critically assess the problem of converting coherence to work. Through a careful account of all resources involved in the thermodynamic transformations within a fully quantum-mechanical treatment, we show that there exist thermal machines extracting work from coherence arbitrarily well. Such machines only need to act on individual copies of a state and can be reused. On the other hand, we show that for any thermal machine with finite resources not all the coherence of a state can be extracted as work. However, even bounded thermal machines can be reused infinitely many times in the process of work extraction from coherence.

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Kamil Korzekwa, Matteo Lostaglio, Jonathan Oppenheim, David Jennings. 2015-06-25. The extraction of work from quantum coherence. https://doi.org/10.1088/1367-2630/18/2/023045

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