Proposal for Optical Super-Focusing with a Metal-Dielectric Waveguide Array

TL;DR

This paper demonstrates a novel super-focusing technique in the visible spectrum using a specially designed metal-dielectric waveguide array, achieving sub-wavelength focusing through radiationless interference.

Contribution

It introduces a new waveguide array design that enables super-focusing at visible wavelengths, extending previous methods to a new regime.

Findings

Achieved focusing to 0.21 of the optical wavelength

Demonstrated the concept using finite-difference time-domain simulations

Focusing occurs at half the optical wavelength from the source

Abstract

In this paper, super-focusing using radiationless electromagnetic interference is extended to the visible regime. It is shown that the highest-order mode of a specifically designed metal-dielectric waveguide array can provide the rapidly oscillating source field for radiationless interference. Using finite-difference time-domain simulations, an example structure is demonstrated. This structure provides focusing to 0.21 of the optical wavelength at a distance of half the optical wavelength from the source.