Depolarization composition of the back-scattered circularly polarized light

TL;DR

This paper investigates how circularly polarized light backscattered from turbid media decomposes into polarized components, revealing the dynamics of polarization memory and implications for tissue polarimetry.

Contribution

It provides a detailed analysis of the polarization decomposition of backscattered light, linking circular polarization memory with helicity flips and polarization states within scattering media.

Findings

Backscattered unpolarized light decomposes into two polarized components with opposite helicities.

Multiple scattering causes superposition, resulting in linear polarization.

Circular polarization memory is linked to helicity conservation within the medium.

Abstract

We consider the origin of unpolarised light resulting from the backscattering of circularly polarized light by random turbid tissue-like disperse medium. We reveal the dynamics of the backscattered fraction of unpolarized light, disclosing its meticulous decomposition into two rigorously polarized components characterized by opposing helicities, with fully defined polarization states. Concurrently, their superposition, driven by multiple scattering within the medium, leads to the appearance of a fraction of linear polarization. We emphasize that in-depth binding of circular polarization memory of light with the helicity flips occurs within the scattering medium, meaning the conservation of spin angular momentum. We anticipate that the results obtained hold significant implications for future studies, particularly in the field of tissue polarimetry and light vortexes.