The diffusive pair contact process and non-equilibrium wetting

TL;DR

This paper maps the pair contact process with diffusion to a KPZ equation in a potential, revealing that its phase transition is a depinning transition, supporting its classification within the DP universality class.

Contribution

It establishes a connection between the PCPD and non-equilibrium wetting through a Cole-Hopf transformation, providing new insights into its phase transition behavior.

Findings

The phase transition in PCPD is a depinning transition.

PCPD belongs to the directed percolation universality class.

The transformation links PCPD to KPZ equation in a potential.

Abstract

The Langevin equation for the pair contact process with diffusion (PCPD) 2A->3A, 2A->0 can be mapped by a Cole-Hopf transformation to a Kardar-Parisi-Zhang equation in a potential which has been discussed previously in the context of non-equilibrium wetting. Using this transformation the phase transition in the PCPD manifests itself as a depinning transition at the borderline of a region of phase coexistence, supporting the conjecture that the PCPD belongs to the DP universality class.