Creation of ray modes by strong random scattering

TL;DR

This paper explores how strong random scattering in systems with degenerate spectra leads to the formation of ray modes, which are extended states with unique transport properties, differing from traditional Anderson localization.

Contribution

It introduces the concept of ray modes created by strong scattering, highlighting their geometric nature and universal dynamics, a novel phenomenon in disordered systems with degeneracies.

Findings

Ray modes are formed under strong random scattering.

These states exhibit Fokker-Planck dynamics with universal drift and diffusion.

Behavior resembles edge states in quantum Hall systems.

Abstract

In the presence of strong random scattering the behavior of particles with degenerate spectra is quite different from Anderson localization of particles in a single band: it creates geometric states rather than confining the particles to an area of the size of the localization length. These states are subject to a Fokker-Planck dynamics with universal drift velocity and disorder dependent diffusion coefficient. This behavior has some similarity with the unidirectionally propagating edge states in quantum Hall systems.