Coherent multiple scattering of light in (2+1) dimensions

TL;DR

This paper develops a comprehensive multiple scattering theory for light in (2+1)D disordered media, revealing a transition from scalar to vector regimes affecting polarization and coherent backscattering.

Contribution

It introduces a formalism that fully accounts for the vector nature of light without paraxial approximation in (2+1)D disordered media.

Findings

Identifies a crossover from scalar to vector regimes in light scattering.

Shows polarization randomization affects the coherent backscattering peak.

Provides a detailed distribution of transverse momenta evolution.

Abstract

We formulate a multiple scattering theory of light in media spatially disordered along two directions and homogeneous along the third one, without making any paraxial approximation on the wave equation and fully treating the vector character of light. With this formalism, we calculate the distribution of transverse momenta of a beam as it evolves along the optical axis, and unveil a phenomenon not captured by the paraxial equation: a cross-over from a scalar to a vector regime, visible in the coherent backscattering peak as polarization gets randomized.