Nonlinear Pattern Formation in Active Optical Systems: Shocks, Domains of Tilted Waves, and Cross-Roll Patterns

Vortices, shocks, domains of tilted waves, and cross-roll patterns are typical patterns of the complex Swift-Hohenberg equation, which describes spatiotemporal dynamics in nonlinear optical systems of large Fresnel number, such as lasers, optical parametric oscillators, and photorefractive oscillators. We show the occurrence of such ``essentially nonlinear'' patterns experimentally on a photorefractive oscillator and compare it with numerical solutions of the complex Swift-Hohenberg equation.