A unified analytical model for extraordinary transmission in subwavelength metallic gratings

TL;DR

This paper introduces a unified analytical model explaining extraordinary optical transmission in metallic gratings, emphasizing standing wave resonances over surface plasmon effects, applicable across various geometries and polarizations.

Contribution

The authors develop an intuitive, unified analytical framework for EOT that applies to different geometries, polarizations, and spectral regimes, without relying on surface plasmon assumptions.

Findings

Model accurately predicts EOT resonance conditions.

Applicable to both TE and TM polarizations.

Works in subwavelength and non-subwavelength regimes.

Abstract

We present an intuitive analytical model for extraordinary optical transmission (EOT) through corrugated metallic films. In the framework of this model, EOT emerges from standing wave resonances of the different diffraction orders, and is an inherent property of periodic structures, which does not require specific polarization dependent properties such as surface plasmons. The model correctly predicts the conditions for the EOT resonances in various geometrical configurations, in both TE and TM polarizations,and in the subwavelength and non-subwavelength spectral regimes, using the same underlying mechanism.