Fluctuations of work in realistic equilibrium states of quantum systems with conserved quantities

TL;DR

This paper investigates how conserved quantities influence the fluctuations in measurements of small quantum systems out of equilibrium, using numerical simulations of the Dicke model to reveal their impact on relaxation and fluctuations.

Contribution

It provides new numerical evidence on the role of conserved charges in out-of-equilibrium quantum dynamics of few-body systems.

Findings

Conserved quantities significantly affect measurement fluctuations.

Realistic equilibrium states exhibit distinct fluctuation patterns.

Numerical results highlight the importance of charges in relaxation processes.

Abstract

The out-of-equilibrium dynamics of quantum systems is one of the most fascinating problems in physics, with outstanding open questions on issues such as relaxation to equilibrium. An area of particular interest concerns few-body systems, where quantum and thermal fluctuations are expected to be especially relevant. In this contribution, we present numerical results demonstrating the impact of conserved quantities (or 'charges') in the outcomes of out-of-equilibrium measurements starting from realistic equilibrium states on a few-body system implementing the Dicke model.