Impact of imbalancing in the self-splitting of beams with nested vortices into solitons in quadratic non-linear crystals

Abstract

We address the existence and instability of bright vortex solitary waves in quadratic non-linear media under conditions for Type II second-harmonic generation and study in detail the effects introduced by the presence of power imbalancing at the fundamental frequency. We find the families of solitary-wave solutions with different combinations of topological charges of the nested vortices and show their spontaneous azimuthal instability. The growth rates of the azimuthal perturbations are calculated as a function of the imbalancing. Experimental consequences are stressed and discussed. © 1998 Elsevier Science B.V. All rights reserved.