Design and analysis of a nanostructure grating based on a hybrid plasmonic slot waveguide

A novel nanostructure grating with broadband reflection is proposed and analyzed in this paper. The grating is based on a hybrid plasmonic slot waveguide that consists of a vertical dielectric-slot incorporated at the gap between the upper silicon rib and the metal substrate. The structure could provide an ultra-tight mode confinement in the cross-section while maintaining a relatively low propagation loss. By exploiting the superior modal properties, an ultra-compact and broadband Bragg grating is presented, which shows the capability of efficient wavelength selection near the telecom bandwidths. The waveguide-based Bragg grating could be used as a filter in telecommunication systems and could be a promising candidate for future integrated photonic circuits.