A general framework for multiple scattering of polarized waves including anisotropies and Berry phase

TL;DR

This paper introduces a comprehensive framework for modeling multiple scattering of polarized waves in complex media, incorporating anisotropies and Berry phase effects, and providing a unified approach for various scattering phenomena.

Contribution

It presents a novel, general theoretical framework that accounts for anisotropies and Berry phase in multiple scattering of polarized waves, using a local frame and Wigner D-matrices.

Findings

Framework captures Berry phase effects in scattering.

Unified formalism for multiple anisotropies like dichroism and birefringence.

Solution via linear algebra simplifies complex scattering calculations.

Abstract

We develop a framework for the multiple scattering of a polarized wave. We consider particles with spin propagating in a medium filled with scatterers. We write the amplitudes of each spin eigenstate in a local, mobile frame. One of the axes is in the direction of propagation of the particle. We use this representation to define a directional Green's operator of the homogeneous medium and also to write the spin-dependent scattering amplitudes. We show that this representation reveals a Berry phase. We establish a generalized Green-Dyson equation for the multiple scattering problem in this framework. We show that the generalized Green-Dyson equation can be solved by linear algebra if one uses a representation of the rotations based on Wigner D-matrices. The properties of light scattering are retrieved if we use spin 1 particles. Our theory allows to take into account several kinds of anisotropies like circular or linear dichroism and birefringence, Faraday effects andMie scattering within the same formalism. Several anisotropies can be present at the same time.