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arXiv · 1508.04128

When is a quantum heat engine quantum?

Alexander Friedenberger·Eric Lutz
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Abstract

Quantum thermodynamics studies quantum effects in thermal machines. But when is a heat engine, which cyclically interacts with external reservoirs that unavoidably destroy its quantum coherence, really quantum? We here use the Leggett-Garg inequality to assess the nonclassical properties of a single two-level Otto engine. We provide the complete phase diagram characterizing the quantumness of the engine as a function of its parameters and identify three distinct phases. We further derive an explicit expression for the transition temperature.

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Alexander Friedenberger, Eric Lutz. 2015-08-17. When is a quantum heat engine quantum?. https://doi.org/10.1209/0295-5075/120/10002

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