Vertically oriented, three-dimensionally tapered deep-subwavelength metallic nanohole arrays developed by photofluidization lithography.

The field-gradient, superficial photo fluidization of azomaterials allows a specific 3D nano-silhouette to be shaped over a large area, so as to get easy access to a 3D-tapered, deep sub-wavelength Au nanohole (20 nm spatial size) array. The squeezing of visible light into the deep sub-wavelength point and the relevant extraordinary optical transmission (EOT) are achieved using this 3D-tapered, 20 nm Au nanohole.