Spoof surface plasmons on the dielectric-loaded doubly-corrugated grating for Terahertz applications

Abstract

Spoof surface plasmons (SSP) on the corrugated metal surfaces has attracted enormous attentions due to its many extraordinary properties and can find a variety of applications in microwave and terahertz (THz) community. In this paper, we present a theoretical and numerical study of SSP mode on the dielectric-loaded double-corrugated gratings. General SSP dispersion theory is developed by a simplified modal expansion method on the structure which is also verified in THz band. In our referred structure, symmetric SSP mode demonstrates lower propagation loss compared with the other anti-symmetric SSP mode. Our studies about SSP modes on the dielectric-loaded doubly corrugated grating can provide new ways to realize both extreme sub-wavelength confinement and low propagation loss. Potential applications include low loss waveguide and circuitry, sensitive sensing and novel electronic sources induced by injected electron beam, etc.