Dynamic versus Anderson wavepacket localization

TL;DR

This paper compares dynamic and Anderson wavepacket localization mechanisms, showing how disorder causes a transition from resonant dynamic localization to dominant Anderson localization in waveguide arrays.

Contribution

It demonstrates the transition from dynamic to Anderson localization in waveguide arrays due to disorder, highlighting the dominance of Anderson localization.

Findings

Disorder causes a gradual transition from dynamic to Anderson localization.

Anderson localization becomes dominant when disorder is sufficiently strong.

Resonant effects are negligible in the Anderson regime.

Abstract

We address the interplay between two fundamentally different wavepacket localization mechanisms, namely resonant dynamic localization due to collapse of quasi-energy bands in periodic media and disorder-induced Anderson localization. Specifically, we consider light propagation in periodically curved waveguide arrays on-resonance and off-resonance, and show that inclusion of disorder leads to a gradual transition from dynamic localization to Anderson localization, which eventually is found to strongly dominate. While in the absence of disorder, the degree of localization depends critically on the bending amplitude of the waveguide array, when the Anderson regime takes over the impact of resonant effects becomes negligible.