MULTIPLE-CHARGED OPTICAL VORTEX SOLITONS IN BULK KERR MEDIA

We investigate numerically Optical Vortex Solitons (OVSs) with differe nt topological charges (m) and show that they are characterised with s oliton constants equal to the product of their topological charge and the soliton constant of unit OVS. The propagation characteristics for \m\ = 1,2,3 and 4 are investigated. We proposed an approximate analyti cal description of the field distribution, which was found to be adequ ate to describe multiple-charged solitons. The instability of these so litons is discussed and they were found to be unstable in the presence of a perturbation. (C) 1997 Elsevier Science B.V.