Tunable multiple soliton generation in Kerr media

Optical solitons are self-confined robust beams existing in various kind of nonlinear media; their studies are of fundamental as well as technological relevance. The generation of multiple solitons has been studied using modulational instability, or from shock waves emerging from either bright or dark input beams propagating in dispersive media. We propose a novel route for the generation of multiple solitons using a broad beam launched into a nonlinear medium with a modified distribution of the linear refractive index, i.e. a defect. When the size of the input beam is large compared with the defect width, defect induced modulation in the phase of the beam will result in the formation of multiple fringes. These fringes can evolve into multiple interacting solitons depending on beam excitation level. The number of fringes can be controlled by the height of the defect (i.e. index jump) as well as the ratio between the widths of the beam and of the defect.