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arXiv · 2012.13640

Alternative experimental ways to access entropy production

Zheng Tan·Patrice A. Camati·Guillaume Coeuret Cauquil·Alexia Auffèves·Igor Dotsenko
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Abstract

We theoretically derive and experimentally compare several different ways to access entropy production in a quantum process under feedback control. We focus on a bipartite quantum system realizing an autonomous Maxwell's demon scheme reported by Najera-Santos et al. [Phys.~Rev.~Research 2, 032025(R) (2020)], where information encoded in a demon is consumed to transfer heat from a cold qubit to a hot cavity. By measuring individual quantum trajectories of the joint demon-cavity-qubit system, we compute the entropy production with six distinct expressions derived from different approaches to the system description and its evolution. Each method uses a specific set of trajectories and data processing. Our results provide a unified view on the various meanings of irreversibility in quantum systems and pave the way to the measurement of entropy production beyond thermal frameworks.

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Zheng Tan, Patrice A. Camati, Guillaume Coeuret Cauquil, Alexia Auffèves, Igor Dotsenko. 2020-12-25. Alternative experimental ways to access entropy production. https://doi.org/10.1103/physrevresearch.3.043076

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