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arXiv · 1804.06873

Entropy Dynamics in the System of Interacting Qubits

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

The classical Second Law of Thermodynamics demands that an isolated system evolves with a non-diminishing entropy. This holds as well in quantum mechanics if the evolution of the energy-isolated system can be described by a unital quantum channel. At the same time, the entropy of a system evolving via a non-unital channel can, in principle, decrease. Here, we analyze the behavior of the entropy in the context of the H-theorem. As exemplary phenomena, we discuss the action of a Maxwell demon (MD) operating a qubit and the processes of heating and cooling in a two-qubit system. We further discuss how small initial correlations between a quantum system and a reservoir affect the increase in the entropy under the evolution of the quantum system.

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N. S. Kirsanov, A. V. Lebedev, M. V. Suslov, V. M. Vinokur, G. Blatter, G. B. Lesovik. 2018-04-18. Entropy Dynamics in the System of Interacting Qubits. https://doi.org/10.1007/s10946-018-9698-0

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