Singular polarimetry: Evolution of polarization singularities in electromagnetic waves propagating through a weakly anisotropic medium

TL;DR

This paper analyzes how polarization singularities in electromagnetic waves evolve as they propagate through weakly anisotropic media, providing analytical solutions and specific examples of vortex unfolding in birefringent and dichroic environments.

Contribution

It introduces an analytical approach to describe the evolution of polarization singularities in non-uniform fields within weakly anisotropic media.

Findings

Analytical solutions for polarization evolution in homogeneous media.

Visualization of C-lines and L-surfaces in polarization distributions.

Examples of vortex unfolding in birefringent and dichroic media.

Abstract

We describe the evolution of a paraxial electromagnetic wave characterizing by a non-uniform polarization distribution with singularities and propagating in a weakly anisotropic medium. Our approach is based on the Stokes vector evolution equation applied to a non-uniform initial polarization field. In the case of a homogeneous medium, this equation is integrated analytically. This yields a 3-dimensional distribution of the polarization parameters containing singularities, i.e. C-lines of circular polarization and L-surfaces of linear polarization. The general theory is applied to specific examples of the unfolding of a vectorial vortex in birefringent and dichroic media.