Design of tunable optical cavity based on near-field optical coupling between subwavelength periodic nanostructures

The design of a tunable resonant cavity optical filter based on variable near-field coupling between nanostructured gratings is presented. The study shows that as the functionality of the device depends primarily on lateral rather than longitudinal movement of the nanostructured gratings with respect to each other, an optical filter based on this approach could benefit from implementation using MEMS technology.