Finite size effects in nonequilibrium wetting

TL;DR

This paper investigates finite size effects in nonequilibrium wetting models, revealing that phase transitions in finite systems are characterized by a random walk of the average interface height at criticality, with unique finite size scaling features.

Contribution

The study provides an exact analysis and numerical simulations showing the nature of phase transitions in finite nonequilibrium wetting systems and their finite size scaling properties.

Findings

Finite systems exhibit phase transitions characterized by a random walk of the interface height.

The transition does not distinguish between bounded-KPZ and bounded-EW classes.

Finite size scaling in bKPZ classes shows peculiar features compared to other universality classes.

Abstract

Models with a nonequilibrium wetting transition display a transition also in finite systems. This is different from nonequilibrium phase transitions into an absorbing state, where the stationary state is the absorbing one for any value of the control parameter in a finite system. In this paper, we study what kind of transition takes place in finite systems of nonequilibrium wetting models. By solving exactly a microscopic model with three and four sites and performing numerical simulations we show that the phase transition taking place in a finite system is characterized by the average interface height performing a random walk at criticality and does not discriminate between the bounded-KPZ classes and the bounded-EW class. We also study the finite size scaling of the bKPZ universality classes, showing that it presents peculiar features in comparison with other universality classes of nonequilibrium phase transitions.