Propagation of spectral Stokes singularities of stochastic electromagnetic beams through atmospheric turbulence

Abstract

The propagation of spectral Stokes singularities (vortices) of stochastic electromagnetic vortex beams through atmospheric turbulence is studied, where the electromagnetic Gaussian Schell-model (GSM) vortex beam is taken as an illustrative example. It is shown that the spectral Stokes vortices S12 (C-points), S23 and S31 introduced to describe the polarization singularities of stochastic electromagnetic beams appear in turbulence. The motion, creation, annihilation and polarization changes of S12, S23 and S31 vortices, as well as the handedness inversion of S12 vortices may appear as the propagation distance or one beam parameter varies. In the process the topological relationship holds true. In comparison with the free-space propagation, the variation of the refractive index structure constant \(C_{n}^{2}\) in atmospheric turbulence results in similar effects as above. The dependence of S12, S23 and S31 vortices on the propagation distance and beam and turbulence parameters are illustrated by numerical examples.