Nanostructures for very broadband or multi-frequency transition from wave beams to a subwavelength light distributions

TL;DR

This paper introduces a tapered plasmonic nanostructure that efficiently transitions incident wave beams into highly localized, broadband, or multi-frequency light distributions, with potential applications in nanophotonics and optical circuits.

Contribution

The study proposes a novel tapered plasmonic nanostructure capable of broadband or multi-frequency wave-to-light transition, supported by theoretical analysis of its waveguide mode properties.

Findings

Achieves broad frequency range for wave-to-subwavelength light conversion

Maintains a stable localized field near the structure's contour

Potential applications in near-field microscopy and optical nanocircuits

Abstract

In this paper we suggest and theoretically study a tapered plasmonic nanostructure which connects the incident wave beam with a subwavelength spatial region where the field is locally enhanced in a broad frequency range or for different operation frequencies. This spatial region has a frequency stable location near the contour of the tapered structure. This results from a special waveguide mode which can also exist in the tapered structure. We foresee many possible applications for our structure from prospective near-field scanning optical microscopes to interconnects between conventional optical waveguides and prospective optical nanocircuits.