Abstract

In a self-defocusing media transverse instability of dark solitary stripe results in the generation of an optical vortex soliton (OVS). These solitons are (2+l)-dimensional (two "transverse" and a propagation dimension) stationary beam structures with phase singularity and nonzero angular momentum. An OVS is a dark spot, i.e., a zero intensity center surrounded by a bright infinite background. Self-focusing media supports also localized soliton solutions with phase dislocation surrounded by one or many bright rings. To distinguish these solitonic structures from OVS which have nonzero asymptotes at infinity we term them as localized optical vortex solitons (LOVS). Either OVS or LOVS can be generated using an input light beam with an externally superimposed vortex structure. At the singularity the field amplitude is strictly zero while the phase becomes undetermined. Angular momentum of the beam is proportional to mN, where N is the beam power and integer m defines its topological charge.

© 2001 EPS