Generation of elliptical perfect optical vortex beams and their propagation in free-space.

Abstract

We investigate the generation of an elliptical perfect optical vortex (EPOV) beam through the optical Fourier transformation of an elliptical Bessel-Gaussian beam and derive an analytical expression for its complex field amplitude. Our analysis includes the examination of the beam's propagation in free-space and the influence of topological charge on its transmission. The EPOV beam's propagation in free-space can be categorized into non-diffracting and diffracting stages. During the non-diffracting stage, the beam intensity and profile size are effectively preserved over a short transmission distance. Subsequently, in the diffracting stage, the beam profile initially contracts and then expands with a change in the beam intensity. Notably, the impact of topological charge on the beam intensity and profile size varies across different stages of propagation. We compare our results with those of the circular perfect optical vortex beam propagating in free-space, observing that the EPOV beam exhibits non-diffracting behavior for short propagation distances compared to its circular counterpart. The signature of the focusing behavior of the EPOV beam is observed at a relatively small propagation distance compared to the circular case.