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arXiv · 1906.12163

Steering heat engines: a truly quantum Maxwell demon

Konstantin Beyer·Kimmo Luoma·Walter T. Strunz
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Abstract

We address the question of verifying the quantumness of thermal machines. A Szilárd engine is truly quantum if its work output cannot be described by a local hidden state (LHS) model, i. e. an objective local statistical ensemble. Quantumness in this scenario is revealed by a steering-type inequality which bounds the classically extractable work. A quantum Maxwell demon can violate that inequality by exploiting quantum correlations between the work medium and the thermal environment. While for a classical Szilárd engine an objective description of the medium always exists, any such description can be ruled out by a steering task in a truly quantum case.

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Konstantin Beyer, Kimmo Luoma, Walter T. Strunz. 2019-11-26. Steering heat engines: a truly quantum Maxwell demon. https://doi.org/10.1103/physrevlett.123.250606

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