Effect of a Vertical Stack of Aligned Subwavelength Metal Hole Arrays on Extraordinary Transmission Spectra

摘要

We report on the effect of stacking a pair of metallic subwavelength hole arrays on the extraordinary transmission spectrum. A novel fabrication process was developed to create a self-aligned vertical stack of subwavelength metal gratings with precise control of the separation between the two metal films. For separations within the coupling region of the evanescent surface modes of the metal films, minor sharpening of the transmission filter characteristics was observed.