Order and symmetry-breaking in the fluctuations of driven systems

N. Tizón-Escamilla, C. Pérez-Espigares, P. L. Garrido, P. I. Hurtado

Published 2016-06-23Version 1

Dynamic phase transitions (DPTs) at the fluctuating level are one of the most intriguing phenomena of nonequilibrium physics, but their nature in realistic high-dimensional systems remains puzzling. Here we observe for the first time a DPT in the current statistics of an archetypal two-dimensional ($2d$) driven diffusive system, and characterize its properties using macroscopic fluctuation theory. The complex interplay among the external field, anisotropy and currents in $2d$ leads to a rich phase diagram, with different symmetry-broken fluctuation phases separated by lines of $1^{\text{st}}$- and $2^{\text{nd}}$-order DPTs. Order in the form of coherent jammed states emerges to hinder transport for low-current fluctuations, revealing a deep connection between rare events and self-organized structures which enhance their probability, an observation of broad implications.