Multi-hump optical solitons in a saturable medium

Abstract
We investigate multi-hump spatial solitary waves and multi-soliton patterns generated by an incoherent interaction of two optical beams in a medium with saturable (e.g. photorefractive) nonlinearity. Applying a bifurcation analysis and numerical relaxation technique, we reveal different scenarios of creating the multi-hump solitons and find the families of solitary waves composed of two mutually coupled components. We analyse the stability of these solitons to propagation and find that the evolution of a soliton is governed by its modal structure.