Characteristics of partially coherent Laguerre-Gaussian vortex beams propagating in strongly nonlocal nonlinear media.

The analytical propagation formulae of partially coherent Laguerre-Gaussian (LG) vortex beams in strongly nonlocal nonlinear media (SNNM) are derived, which reduce to those of partially coherent standard and elegant LG vortex beams. It is shown that an optical soliton cannot be formed in SNNM because of the self-filling feature of partially coherent LG vortex beams. However, an optical breather is formed for partially coherent LG vortex beams in SNNM, and the hollow beam profile is filled periodically on propagation due to beam coherence. For partially coherent LG vortex beams in SNNM, the degree of hollowness increases as the coherence degree decreases or the topological charge decreases. In particular, it is found that an optical soliton can be formed in SNNM for fully coherent standard LG vortex beams, but cannot be formed for fully coherent elegant ones.