Spatial Dissipative Solitons with Intra-Cavity Photonic Crystals

Here we extend previous analysis to regimes of bistable behaviour. Close to sub-critical modulational instabilities there are narrow regions where both the fundamental and patterned solutions are stable. Standard cavity solitons appear in the parameter regimes corresponding to these regions. The introduction of an intra-cavity photonic crystal can, on one side, suppress completely these bistable regions but can also induce entirely new ones. For example, in a Kerr cavity with a transversally modulated refractive index, we identify a novel bistable region involving a nonlinear pattern for moderately high input powers. In this region the fundamental (low amplitude) solution, otherwise unstable, is stabilized by the photonic crystal through a locking mechanism. Such region is much wider in parameter space (of at least a factor 10) than similar bistable regimes without photonic crystals.