A parametric study of the lensing properties of dodecagonal photonic quasicrystals

TL;DR

This paper investigates the lensing capabilities of 2D photonic quasicrystal slabs with 12-fold symmetry, revealing their dependence on local symmetry and thickness, and highlighting unique focusing and beaming effects.

Contribution

It provides a detailed numerical analysis of PQC slabs, clarifying the role of local symmetry and slab parameters in their focusing properties, and identifying novel effects like sub-wavelength focusing.

Findings

Focusing effects are linked to local symmetry points.

Focusing persists in slabs with reduced width.

Beaming effects are observed in PQC slabs.

Abstract

We present a study of the lensing properties of two-dimensional (2-D) photonic quasicrystal (PQC) slabs made of dielectric cylinders arranged according to a 12-fold-symmetric square-triangle aperiodic tiling. Our full-wave numerical analysis confirms the results recently emerged in the technical literature and, in particular, the possibility of achieving focusing effects within several frequency regions. However, contrary to the original interpretation, such focusing effects turn out to be critically associated to local symmetry points in the PQC slab, and strongly dependent on its thickness and termination. Nevertheless, our study reveals the presence of some peculiar properties, like the ability to focus the light even for slabs with a reduced lateral width, or beaming effects, which render PQC slabs potentially interesting and worth of deeper investigation. Key words: Photonic quasicrystals; negative refraction; superlensing.