Influence of surface plasmon polaritons on light transmission through metallic nanoslits

Abstract

We clarify the positive and the negative roles of a surface plasmon polariton in light transmission through metallic nanoslit/hole structures. While conventional surface plasmon polaritons suppress the transmission due to the equipartition of diffraction orders, we show. that "radiation dressed" surface plasmon polaritons (DSPP) mediate the extraordinary transmission. We determine the coupling strength of DSPP to radiation as a product of the geometric opening ratio, the aperture momentum, and the Fabry-Perot factor and show that the coupling can cause red, blue, or even bi-chromatic shifts of DSPP peaks. The relations between Fabry-Perot and the surface plasmonic resonances as well as slit v.s. hole structures are explained.