Elliptical basis deterministic vortex beams

Singularities in partially coherent beams are usually non-deterministic, i.e., they are singularities of the two-point correlation function, and their measured position depends on the choice of observation point. However, there are a number of ways in which a beam can be constructed to manifest a deterministic vortex on the beam axis. In this paper, we introduce a new approach for making a deterministic vortex beam using an incoherent superposition of elliptical Laguerre-Gaussian (LG) beams. The resulting partially coherent beam manifests a deterministic on-axis vortex both in the source plane and in the far zone. Such deterministic vortices could be used as information carriers in free-space optical communications.