Symmetry Breaking and Vortices in a Sodium-filled Fabry-Pérot Resonator

In the last few years it has been found, both theoretically and experimentally, that interactions among different transverse modes may produce complicated patterns, vortices and spatiotemporal chaos in active and passive optical systems [1]. In a passive nonlinear resonator with high Fresnel number but where only a few modes are selectively excited, symmetry broken patterns and vortices have been observed. We find that, in our system, the total number of vortices in any one pattern is generally small and the total topological charge is zero. Among the symmetry broken structures observed in our experiments, we find a recurrent sequence that is similar to one particular sequence observed in an experiment performed in a laser.