Nanogroove array on thin metallic film as planar lens with tunable focusing
arXiv:1212.5122 · doi:10.1016/j.physleta.2011.11.002
Abstract
Numerical results for the distributions of light transmitted through metallic planar lenses composed of symmetric nanogroove arrays on the surfaces of a gold film are presented and explained. Both the near- and far-field distributions of the intensity of light transmitted are calculated by using a Green's function formalism. Results for an optimal transverse focus based on a quadratic variation of groove width are obtained. Meanwhile, a significant dependence of the focal length on the wavelength of light incident from the air side through the gold film into a dielectric substrate is found for this detector configuration.
14 pages, 6 figures