Topological charges shift of vectorial nonparaxial vortex beam

Based on the vectorial Rayleigh diffraction integral, the analytical propagation expression of a nonparaxial vectorial vortex beam carrying orbital angular momentum (OAM), diffracted at a circular aperture, is presented. The effects of both f parameter and topological charge (m) on the nonparaxiality of apertured vectorial vortex beams are studied. Simulation results show that the topological charge of transverse field component m will shift to m-1, for that of longitudinal field component.