Recurrent scattering and memory effect at the Anderson localization transition

TL;DR

This paper investigates ultrasonic wave propagation in a strongly scattering medium, revealing a large memory effect and recurrent scattering paths that change notably near the Anderson localization transition, providing insights into wave localization phenomena.

Contribution

It demonstrates the presence of a deterministic memory effect and recurrent scattering contributions in ultrasonic measurements, highlighting their behavior near the Anderson localization transition.

Findings

Memory effect is significantly large due to recurrent trajectories.

Recurrent scattering probability decreases with time, changing near the transition.

Dominance of intense recurrent paths near the mobility edge.

Abstract

We report on ultrasonic measurements of the propagation operator in a strongly scattering mesoglass. The backscattered field is shown to display a deterministic spatial coherence due to a remarkably large memory effect induced by long recurrent trajectories. Investigation of the recurrent scattering contribution directly yields the probability for a wave to come back close to its starting spot. The decay of this quantity with time is shown to change dramatically near the Anderson localization transition. The singular value decomposition of the propagation operator reveals the dominance of very intense recurrent scattering paths near the mobility edge.