Key points are not available for this paper at this time.
The fast contraction, or pinching, of optical vortices in both thermal and Kerr self-defocusing media is investigated by numerical techniques. For the thermal case, heat diffusion across the vortex core is described, and the heretofore unexplained stability of optical-vortex solitons in thermal media is explained.
Deykoon et al. (Fri,) studied this question.