In-plane plasmonic modes in a quasicrystalline array of metal nanoparticles

TL;DR

This paper explores in-plane plasmonic modes in a 2D quasicrystalline array of metal nanoparticles, revealing highly localized anti-phase ring modes with potential applications in plasmonic devices.

Contribution

It introduces a simplified eigen-decomposition method leveraging rotational symmetry to analyze plasmonic modes in quasicrystals, identifying unique radial and tangential anti-phase ring modes.

Findings

Anti-phase ring modes exhibit highest spatial localization.

Tangential polarized mode has highest fidelity among leaky modes.

Collective vortex and radial modes have potential applications in plasmonic devices.

Abstract

We investigated the plasmonic modes in a two-dimensional quasicrystalline array of metal nanoparticles. The polarization of the modes is in the array plane. A simplified eigen-decomposition method is presented with the help of rotational symmetry. Two kinds of anti-phase ring modes with radial and tangential polarizations are of highest spatial localizations among all of plasmonic modes. For the leaky characteristic of the anti-phase ring modes, the highest fidelity mode is found to be tangential polarized mode in the quasicrystal array, whereas normal-to-plane polarized mode in the solo ring. The leaky characteristics and spatial localizations of other plasmonic modes are also studied, for example, collective vortex mode that may be potentially useful to form negative responses in plasmonic device, and collective radial mode that may be used to generate light sources with radial polarizations.