Transmission modulation through sub-wavelength hole arrays in metal-VO$_{2}$ double-layer nanostructures

Nanoscale optical systems require active devices able to control light in sub-wavelength structures. We report the use of a unique double layer structure which provides this function. Enhanced transmission of near-infrared light through a subwavelength hole arrays patterned in Ag-VO$_{2 }$and Au-VO$_{2}$ double-layer films shows that it is possible to modulate transmitted intensity by means of a semiconductor-to-metal phase transition in VO$_{2}$. The transmitted intensity in the near-infrared for the metallic phase of VO$_{2}$ is a factor of $\sim $10 greater than the intensity for the semiconducting phase. We explain this modulation in terms of the switchable permittivity difference of the VO$_{2}$ phases.