Kinetics of domain walls in the degenerate optical parametric oscillator

The kinetics of the domain walls that occur in the degenerate optical parametric oscillator are studied within the propagation model. The formation of large intensity peaks for null and positive signal mistuning is shown to be associated with a dynamical scaling law ~ t 1/3 . In the parameter range where the degenerate optical parametric operator reduces to potential systems, the growth law ~ t 1/2 is observed. It is also obtained for negative mistuning of order unity, and up to three times above the threshold, i.e. beyond the validity range of the Swift-Hohenberg model equation. In addition, we describe the labyrinth formation which displays self-similar growth with the law ~ t 1/5 .