Surface Shape Resonances in Lamellar Metallic Gratings
Surface Shape Resonances in Lamellar Metallic Gratings
The specular reflectivity of lamellar gratings of gold with grooves $0.5\ensuremath{\mu}\mathrm{m}$ wide separated by a distance of $3.5\ensuremath{\mu}\mathrm{m}$ was measured on the 2000-- $7000{\mathrm{cm}}^{\ensuremath{-}1}$ spectral range for p-polarized light. Experimental evidence of the excitation of electromagnetic surface shape resonances for optical frequencies is given. In these resonances the electric field …