Surface Plasmons on a Quasiperiodic Grating

TL;DR

This paper introduces a method to calculate surface plasmon frequencies on quasiperiodic surfaces, analyzing how Fibonacci and Thue-Morse sequences affect plasmon dispersion in metals.

Contribution

It presents a novel computational approach for surface plasmons on quasiperiodic profiles, extending previous methods to new complex surface geometries.

Findings

Dispersion relations for Fibonacci and Thue-Morse surface profiles

Surface plasmon frequencies depend on quasiperiodic structure

Method applicable to semi-infinite free-electron metals

Abstract

A method is presented for calculating the frequencies of non-retarded surface plasmons propagating on a semi-inifinite medium with a surface profile described by a one-dimension quasiperiodic function. The profiles are generated, in analogy with previous work on quasiperiodic superlattices, by repeating unitary cells constructed according to an inflation rule. Dispersion relations are obtained for a semi-infinite free-electron metal as the active medium, with surface profiles obeying the Fibonacci and Thue-Morse sequences.