Model for nonequilibrium wetting transitions in two dimensions

A simple two-dimensional (2D) model of a phase growing on a substrate is introduced. The model is characterized by an adsorption rate q, and a desorption rate p. It exhibits a wetting transition which may be viewed as an unbinding transition of an interface from a wall. For p = 1, the model may be mapped onto an exactly soluble equilibrium model exhibiting complete wetting with critical exponents gamma = 1/3 for the diverging interface width and x(0) = 1 for the zero-level occupation. For 0 < p not equal 1 a crossover to different exponents is observed which is related to a Kardar-Parisi-Zhang-type nonlinearity.