Optical sprinklers

Summary form only given. The mean-field model of a degenerate optical parametric oscillator (DOPO) is known to exhibit pattern formation at threshold for negative signal detunings. On the other hand, for positive detunings there are two stable, equivalent, spatially-homogeneous solutions which may be connected by domain walls. In one transverse dimension these walls are stable and stationary. In two dimensions, however, a domain of one solution embedded in the other will shrink due to curvature effects. We show here that by using input pump beams formed by Gauss-Laguerre modes with zero radial index and azimuthal index m/spl ne/0, single and multiple domain walls can be asymptotically trapped in the signal output beam. Several configurations of regularly and irregularly spaced domain walls can be generated with either m=1 or m=2. A collection of optical sprinklers is obtained by numerically integrating the partial differential equations of a DOPO in the presence of diffraction.