In this paper we report an experimental and theoretical study of the optical properties of metallodielectric gratings with subwavelength gaps in the thin metal limit. A mask-free method of fabrication for large area submicron silver gratings on silica substrates has been developed using soft-lithographic techniques. By measuring the zeroth-order transmission of these gratings, both an edge anomaly associated with the Rayleigh wavelength and a resonant anomaly associated with the excitation of surface plasmons (SPs) are observed. A crossed grating configuration is studied: the presence of the additional crossed grating results in a dramatic widening of the plasmonic band gap relative to that of a 1D grating.
We have demonstrated a method of fabricating long-range arrays of 2D metallic microstructures on glass surfaces and measured the optical resonances of those structures. Gold and silver stripes are fabricated using microcontact printing with PDMS gratings and electroless plating techniques without the use of resist masks or etching. Changing the blaze angle and periodicity of the gratings used to make the PDMS stamps varies the line widths. The optical response of these fabricated transmission gratings was evaluated by measuring the transmission spectra while varying the angle of the incident light.