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

ARRAIS, ERIC G.; TOSCANO, FABRICIO; WISNIACKI, DIEGO A.; RONCAGLIA, AUGUSTO J.

Physical Review E

APS

Año: 2019 vol. 100 p. 52136 - 52148

2470-0045

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.