Guided resonances in photonic quasicrystals

TL;DR

This study demonstrates the existence of guided resonances in photonic quasicrystals, revealing their potential for novel optical device engineering by analyzing their modal structures and transmittance responses.

Contribution

First evidence of guided resonances in aperiodic photonic quasicrystals, expanding understanding of their modal behavior compared to periodic structures.

Findings

Guided resonances are excited in photonic quasicrystals.

Resonances arise from coupling of incident waves with degenerate modes.

Resonances can be modeled with a Fano-like approach.

Abstract

In this paper, we report on the first evidence of guided resonances (GRs) in aperiodically-ordered photonic crystals, tied to the concept of "quasicrystals" in solid-state physics. Via a full-wave numerical study of the transmittance response and the modal structure of a photonic quasicrystal (PQC) slab based on a representative aperiodic geometry (Ammann-Beenker octagonal tiling), we demonstrate the possibility of exciting GR modes, and highlight similarities and differences with the periodic case. In particular, we show that, as for the periodic case, GRs arise from the coupling of the incident plane-wave with degenerate modes of the PQC slab that exhibit a matching symmetry in the spatial distribution, and can still be parameterized via a Fano-like model. Besides the phenomenological implications, our results may provide new degrees of freedom in the engineering of GRs, and pave the way for new developments and applications.