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arXiv · 1804.06886

H-theorem and Maxwell Demon in Quantum Physics

N. S. Kirsanov·A. V. Lebedev·I. A. Sadovskyy·M. V. Suslov·V. M. Vinokur·G. Blatter·G. B. Lesovik
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Abstract

The Second Law of Thermodynamics states that temporal evolution of an isolated system occurs with non-diminishing entropy. In quantum realm, this holds for energy-isolated systems the evolution of which is described by the so-called unital quantum channel. The entropy of a system evolving in a non-unital quantum channel can, in principle, decrease. We formulate a general criterion of unitality for the evolution of a quantum system, enabling a simple and rigorous approach for finding and identifying the processes accompanied by decreasing entropy in energy-isolated systems. We discuss two examples illustrating our findings, the quantum Maxwell demon and heating-cooling process within a two-qubit system.

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N. S. Kirsanov, A. V. Lebedev, I. A. Sadovskyy, M. V. Suslov, V. M. Vinokur, G. Blatter, G. B. Lesovik. 2018-04-22. H-theorem and Maxwell Demon in Quantum Physics. https://doi.org/10.1063/1.5025464

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