Splitting of Light Beams with Phase dislocations into Solitons in Quadratic Nonlinear Media

We investigate the propagation of intense light beams in bulk quadratic nonlinear crystals under conditions for second-harmonic generation. We show numerically that input light beams with a spiral phase front dislocation self-split in the crystal into several spatial solitons. For input fundamental and its second harmonic gaussian beams the latter with a phase dislocation, the number and pattern of output solitons can be controlled by the material and wave parameters involved, and in particular by the input light intensity and by the topological charge of the dislocation. In second harmonic generation processes with a phase dislocation in the input fundamental beam the output pattern of the solitons may be controlled by a low-intensity double frequency gaussian beam.