Light Scattering by Cholesteric Skyrmions

TL;DR

This paper investigates how localized cholesteric liquid crystal excitations, called spherulites, scatter polarized light, providing analytical and numerical insights into their optical cross sections and effects of external fields.

Contribution

It offers a simplified analytical model of cholesteric spherulites and compares approximate and exact numerical methods for light scattering analysis.

Findings

Analytical and numerical cross sections are consistent within the model.

External electric or magnetic fields influence scattering properties.

Potential applications in optical devices are discussed.

Abstract

We study the light scattering by localized quasi planar excitations of a Cholesteric Liquid Crystal known as spherulites. Due to the anisotropic optical properties of the medium and the peculiar shape of the excitations, we quantitatively evaluate the cross section of the axis-rotation of polarized light. Because of the complexity of the system under consideration, first we give a simplified, but analytical, description of the spherulite and we compare the Born approximation results in this setting with those obtained by resorting to a numerical exact solution. The effects of changing values of the driving external static electric (or magnetic) field is considered. Possible applications of the phenomenon are envisaged.