Dynamics and large deviation transitions of the XOR-Fredrickson-Andersen kinetically constrained model

TL;DR

This paper investigates the XOR-FA kinetically constrained model inspired by Rydberg atoms, analyzing its relaxation dynamics and phase transitions between active and inactive states using tensor network methods.

Contribution

It introduces and studies the XOR-FA model, highlighting its unique dynamics and phase transition behavior, distinct from the standard FA model.

Findings

Identification of dynamical phase transitions in XOR-FA model

Relation of XOR-FA dynamics to exclusion processes

Observation of large deviation fluctuations leading to phase changes

Abstract

We study a one-dimensional classical stochastic kinetically constrained model (KCM) inspired by Rydberg atoms in their "facilitated" regime, where sites can flip only if a single of their nearest neighbours is excited. We call this model "XOR-FA" to distinguish it from the standard Fredrickson-Andersen (FA) model. We describe the dynamics of the XOR-FA model, including its relation to simple exclusion processes in its domain wall representation. The interesting relaxation dynamics of the XOR-FA is related to the prominence of large dynamical fluctuations that lead to phase transitions between active and inactive dynamical phases as in other KCMs. By means of numerical tensor network methods we study in detail such transitions in the dynamical large deviation regime.