Plasmonic-dielectric compound grating with high group-index and transmission

TL;DR

This paper introduces a novel plasmonic-dielectric grating system that achieves high group index and transmission by leveraging interference effects, enabling slow light applications.

Contribution

It presents a new compound system combining dielectric gratings and plasmonic cavities, demonstrating enhanced slow light properties and analyzing the effects of structural parameters.

Findings

Group index exceeds 200

Transmission surpasses 75%

Structural parameters influence slow light properties

Abstract

We propose a compound system consisting of a dielectric grating and a plasmonic resonance cavity embedded in the grating. Based on the interference effect between the surface mode supported by the dielectric grating and the plasmonic-induced cavity mode, this system could achieve slow light with group index more than 200 and transmission more than 75%. Meanwhile, we examine the effects of the period numbers of the compound system and photonic crystal superlattice made up of alternate layers of the grating and air on the properties of slow light.