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arXiv · 1907.06285

Work statistics for sudden quenches in interacting quantum many-body systems

Eric G. Arrais·Diego A. Wisniacki·Augusto J. Roncaglia·Fabricio Toscano
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Abstract

Work in isolated quantum systems is a random variable and its probability distribution function obeys the celebrated fluctuation theorems of Crooks and Jarzynski. In this study, we provide a simple way to describe the work probability distribution function for sudden quench processes in quantum systems with large Hilbert spaces. This description can be constructed from two elements: the level density of the initial Hamiltonian, and a smoothed strength function that provides information about the influence of the perturbation over the eigenvectors in the quench process, and is especially suited to describe quantum many-body interacting systems. We also show how random models can be used to find such smoothed work probability distribution and apply this approach to different one-dimensional spin-$1/2$ chain models. Our findings provide an accurate description of the work distribution of such systems in the cases of intermediate and high temperatures in both chaotic and integrable regimes.

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Eric G. Arrais, Diego A. Wisniacki, Augusto J. Roncaglia, Fabricio Toscano. 2019-11-18. Work statistics for sudden quenches in interacting quantum many-body systems. https://doi.org/10.1103/physreve.100.052136

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