Decay of Polarization Singularities of an Erf-Gaussian Beam Due to External Perturbations

This article is devoted to a new direction of modern singular optics—Erf-Gaussian (EG) beams that carry a fractional topological charge. It is shown that Erf-Gaussian beams were generated using an axicon and an anisotropic crystal, and the polarization characteristics of these beams with a fractional topological charge in the vicinity of the beam axis were experimentally studied. Theoretical calculations were confirmed and it was shown that Erf-Gaussian beams introduce changes into the original picture of the polarization distribution, and that the central spiral polarization umbilical splits into two polarization features of the “lemon” type. The method described in the article for generating and analyzing polarization singularity in Erf-Gaussian beams based on a fractional topological charge can be used in optical profilometry to analyze the polarization and phase properties of materials and surface roughness.