Nonequilibrium phase transition on a randomly diluted lattice

TL;DR

This paper investigates a new universality class of nonequilibrium phase transitions in the contact process on diluted lattices, revealing unconventional scaling and Griffiths effects near the percolation threshold.

Contribution

It introduces the critical behavior of the contact process on diluted lattices, highlighting activated scaling and Griffiths effects, and connects to infinite-randomness fixed points.

Findings

Unconventional activated dynamical scaling observed

Strong Griffiths effects identified near the percolation threshold

Critical behavior characterized in 2D and 3D lattices

Abstract

We show that the interplay between geometric criticality and dynamical fluctuations leads to a novel universality class of the contact process on a randomly diluted lattice. The nonequilibrium phase transition across the percolation threshold of the lattice is characterized by unconventional activated (exponential) dynamical scaling and strong Griffiths effects. We calculate the critical behavior in two and three space dimensions, and we also relate our results to the recently found infinite-randomness fixed point in the disordered one-dimensional contact process.