Coherent forward scattering as a signature of Anderson metal-insulator transitions

TL;DR

This paper demonstrates that the coherent forward scattering peak serves as a clear indicator of the Anderson metal-insulator transition, with its behavior revealing critical properties and universality across disorder types.

Contribution

It introduces the CFS peak as a new signature for identifying and analyzing the Anderson transition, linking it to critical exponents and spectral properties.

Findings

CFS peak amplitude jumps at the transition

CFS contrast follows one-parameter scaling

Critical CFS peak relates to spectral compressibility

Abstract

We show that the coherent forward scattering (CFS) interference peak amplitude sharply jumps from zero to a finite value upon crossing a metal-insulator transition. Extensive numerical simulations reveal that the CFS peak contrast obeys the one-parameter scaling hypothesis and gives access to the critical exponents of the transition. We also discover that the critical CFS peak directly controls the spectral compressibility at the transition where eigenfunctions are multifractal, and we demonstrate the universality of this property with respect to various types of disorder.