Stochastic theory of non-equilibrium wetting

¹ Departamento de Física da Faculdade de Ciências e Centro de Física da Matéria Condensada da Universidade de Lisboa Avenida Professor Gama Pinto, 2, P-1643-003 Lisboa Codex, Portugal
² Institute Carlos I for Theoretical and Computational Physics, University of Granada 18071 Granada, Spain
³ Departamento de Electromagnetismo y Física de la Materia, Universidad de Granada 18071 Granada, Spain

Received: 26 March 2001
Accepted: 21 December 2001

Abstract

We study a Langevin equation describing non-equilibrium depinning and wetting transitions. Attention is focused on short-ranged attractive substrate-interface potentials. We confirm the existence of first-order depinning transitions, in the temperature-chemical potential diagram, and a tricritical point beyond which the transition becomes a non-equilibrium complete wetting transition. The coexistence of pinned and depinned interfaces occurs over a finite area, in line with other non-equilibrium systems that exhibit first-order transitions. In addition, we find two types of phase coexistence, one of which is characterized by spatio-temporal intermittency (STI). A finite-size analysis of the depinning time is used to characterize the different coexisting regimes. Finally, a stationary distribution of characteristic triangles or facets was shown to be responsible for the structure of the STI phase.