The exact phase diagram for a class of multispecies asymmetric exclusion processes

TL;DR

This paper derives the exact phase diagram for a multispecies asymmetric exclusion process, revealing new phenomena like zero-density phases and dynamical localisation, advancing understanding of nonequilibrium statistical physics.

Contribution

It provides the first exact phase diagram for a multispecies ASEP with reservoirs, introducing nested fat shocks to explain macroscopic features.

Findings

Identification of zero-density phases for certain species

Discovery of dynamical localisation phenomena

Complete characterization of phase boundaries

Abstract

The asymmetric exclusion process is an idealised stochastic model of transport, whose exact solution has given important insight into a general theory of nonequilibrium statistical physics. In this work, we consider a totally asymmetric exclusion process with multiple species of particles on a one-dimensional lattice in contact with reservoirs. We derive the exact nonequilibrium phase diagram for the system in the long time limit. We find two new phenomena in certain regions of the phase diagram: when the density of a species becomes zero throughout the system, and dynamical localisation when the density of a species is nonzero only within an interval far from the boundaries. We give a complete explanation of the macroscopic features of the phase diagram using what we call nested fat shocks.