Anomalous localization of light in one-dimensional L\'evy photonic lattices

TL;DR

This paper investigates light localization in one-dimensional Levy photonic lattices with heavy-tailed disorder, revealing unique stretched exponential and asymmetric localization profiles supported by experiments and simulations.

Contribution

It introduces a novel inhomogeneous disorder model in photonic lattices and characterizes the resulting anomalous light localization phenomena.

Findings

Light localization follows a stretched exponential profile.

Localized light profiles are asymmetric relative to excitation.

Experimental results align with tight-binding simulations.

Abstract

Localization of coherent propagating waves has been extensively studied over the years, primarily in homogeneous random media. However, significantly less attention has been given to wave localization in inhomogeneous systems, where the standard picture of Anderson localization does not apply, as we demonstrate here. We fabricate photonic lattices with inhomogeneous disorder, modeled by heavy-tailed $\alpha$-stable distributions, and measure the output light intensity profiles. We demonstrate that the spatial localization of light is described by a stretched exponential function, with a stretching parameter $\alpha$, and an asymmetric localized profile with respect to the excitation site. We support our experimental and theoretical findings with extensive tight-binding simulations.