Disorder-induced coherent scattering in slow-light photonic crystal waveguides

TL;DR

This paper investigates how structural disorder affects light transmission in slow-light photonic crystal waveguides, combining experimental measurements with theoretical modeling to understand disorder-induced scattering and localization.

Contribution

It introduces a self-consistent scattering theory based solely on statistical disorder functions, accurately matching experimental results without fitting parameters.

Findings

Disorder causes a transition from well-defined group velocity propagation to disorder-dominated scattering.

Theoretical predictions align closely with experimental data, validating the model.

Insights into light localization and multiple scattering phenomena in slow-light waveguides are provided.

Abstract

We present light transmission measurements and frequency-delay reflectometry maps for GaAs photonic crystal membranes, which show the transition from propagation with a well defined group velocity to a regime completely dominated by disorder-induced coherent scattering. Employing a self-consistent optical scattering theory, with only statistical functions to describe the structural disorder, we obtain an excellent agreement with the experiments using no fitting parameters. Our experiments and theory together provide clear physical insight into naturally occurring light localization and multiple coherent-scattering phenomena in slow-light waveguides.