Design of a Structured Bulk Plasmon Illumination Source for Enhancing Plasmonic Cavity Superlens Imaging

Abstract

A structured bulk plasmon illumination (BPI) source is designed for achieving a uniform high spatial frequency illumination field. By employing the hyperbolic metamaterial (HMM) composed of alternatively stacked metal and dielectric nanolayers, the deep subwavelength bulk plasmon polaritons (BPPs) can be launched. The obtained BPP modes are then utilized as a structured illumination source for improving the imaging resolution. More importantly, the BPI intensity can be improved remarkably by adding an extra Ag layer to the original BPI source. When two nano-slits are illuminated by the BPI source, the imaging resolution of plasmonic cavity superlens is improved obviously. Especially, after adding an extra Ag layer to the original BPI source, one can find the obvious improvement of the image contrast. The proposed BPI source promises some potential in near-field super resolution lithography.