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arXiv · 2005.10523

Information Fluctuation Theorem for an Open Quantum Bipartite System

Jung Jun Park·Hyunchul Nha·Sang Wook Kim·Vlatko Vedral
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Abstract

We study an arbitrary non-equilibrium dynamics of a quantum bipartite system coupled to a reservoir. For its characterization, we present a fluctuation theorem (FT) that explicitly addresses the quantum correlation of subsystems during the thermodynamic evolution. To our aim, we designate the local and the global states altogether in the time-forward and the time-reversed transition probabilities. In view of the two-point measurement scheme, only the global states are subject to measurements whereas the local states are used only as an augmented information on the composite system. We specifically derive a FT in such a form that relates the entropy production of local systems in the time-forward transition to the change of quantum correlation in the time-reversed transition. This also leads to a useful thermodynamic inequality and we illustrate its advantage by an example of an isothermal process on Werner states.

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Jung Jun Park, Hyunchul Nha, Sang Wook Kim, Vlatko Vedral. 2020-05-21. Information Fluctuation Theorem for an Open Quantum Bipartite System. https://doi.org/10.1103/physreve.101.052128

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