Resonant mode approximation of the scattering matrix of photonic crystal slabs near several Wood-Rayleigh anomalies

TL;DR

This paper introduces a resonant mode approximation method for efficiently calculating the scattering matrix of multilayered photonic crystal slabs near Wood-Rayleigh anomalies, enabling faster analysis of high-Q resonances.

Contribution

The paper develops a novel approximation technique for the scattering matrix of photonic crystal slabs near multiple diffraction thresholds, improving computational efficiency.

Findings

Enables fast calculation of scattering matrices near Wood-Rayleigh anomalies.

Accurately describes high-Q resonances such as bound states in the continuum.

Applicable to multilayered periodic structures in optical simulations.

Abstract

The resonant mode approximation of the scattering matrix is considered for calculating the optical properties of multilayered periodic structures within the formalism of the Fourier-modal method for two diffraction thresholds in close proximity of the spectral-angular range of interest. The developed approximation opens up possibilities for the fast calculation of the scattering matrix of these structures when describing the integral characteristics of spectra and dispersion curves containing high-Q resonances, such as bound states in the continuum.