Phase locking in nonlinear optical patterns

We report a new type of optical patterns induced by phase locking of several wave vectors with different lengths and orientations. Wave vector selection is due to the optical nonlinearity provided by a Kerr-like medium. The system displays pattern multistability. We characterize the different configurations by the distribution of wave vector families in Fourier space. Even close to threshold, the strong coupling among families yields a collective behavior without critical slowing down, at variance with the isolated behavior of each separate family.