Quantifying the intrinsic amount of fabrication disorder in photonic-crystal waveguides from optical far-field intensity measurements

TL;DR

This paper introduces an experimental method to quantify fabrication disorder in photonic-crystal waveguides by analyzing far-field measurements of localized modes, achieving sensitivity to nanometer-scale imperfections.

Contribution

The study presents a novel approach to measure intrinsic fabrication disorder in photonic devices using optical far-field data and numerical simulations, enhancing disorder characterization.

Findings

Quantifies disorder down to ~1 nm sensitivity.

Correlates Anderson localization spectral range with fabrication imperfections.

Provides a practical method for assessing nanophotonic device quality.

Abstract

Residual disorder due to fabrication imperfections has important impact in nanophotonics where it may degrade device performance by increasing radiation loss or spontaneously trap light by Anderson localization. We propose and demonstrate experimentally a method of quantifying the intrinsic amount of disorder in state-of-the-art photonic-crystal waveguides from far-field measurements of the Anderson-localized modes. This is achieved by comparing the spectral range that Anderson localization is observed to numerical simulations and the method offers sensitivity down to ~ 1 nm.