Focusing of electromagnetic waves by periodic arrays of dielectric cylinders

TL;DR

This paper demonstrates through numerical simulations that two-dimensional arrays of dielectric cylinders can focus electromagnetic waves, acting as optical lenses, with effectiveness influenced by polarization and disorder robustness.

Contribution

It provides the first detailed numerical evidence that dielectric cylinder arrays can focus electromagnetic waves, supporting recent theoretical conjectures.

Findings

E-polarized waves are easier to focus than H-polarized waves.

Focusing robustness persists despite disorders in the array.

Comparison indicates similarities with acoustic wave focusing.

Abstract

By numerical simulations, we show that properly arranged two dimensional periodic arrays, formed by dielectric cylinders embedded in parallel in a uniform medium, can indeed act as an optical lens to focus electromagnetic waves, in accordance with the recent conjecture in the literature. The numerical simulations are based on an exact multiple scattering technique. The results suggest that the E-polarized waves are easier to be focused than the H-polarized waves. The robustness of the focusing against disorders is also studied. Comparison with the corresponding cases for acoustic waves is also discussed.