Higher-charge vortex solitons and vector vortex solitons in strongly nonlocal media.

We report, to the best of our knowledge, the first experimental observation of higher-charge vortex solitons and vector vortex solitons in lead glass with strongly thermal nonlocal nonlinearity. A higher-charge vortex soliton with a topological charge of l = 4 and a vector vortex soliton consisting of two orthogonally polarized vortex components, with charges l(1) = 1 and l(2) = 4, were observed at several times of diffraction length. We show that the ring profiles and the carried topological charges of the two incoherently coupled vortex components can be preserved. We also numerically find that the stability of the higher-charge vortex can be enhanced by co-propagating a stable, single-charge vortex. (C) 2019 Optical Society of America