A transformation optics approach to singular metasurfaces

TL;DR

This paper investigates how singular geometries in metasurfaces influence surface plasmon behavior, energy concentration, and spectral transitions, revealing new insights into plasmonic excitations on complex metal surfaces.

Contribution

It introduces a transformation optics framework to analyze singular metasurfaces, highlighting their unique plasmonic properties and spectral characteristics compared to regular surfaces.

Findings

Singular metasurfaces support unique plasmonic modes with high energy concentration.

Transition from discrete to continuous spectrum occurs at singularities.

Quantum numbers characterize plasmonic excitations despite surface singularities.

Abstract

Surface plasmons dominate the optical response of metal surfaces, and their nature is controlled by surface geometry. Here we study metasurfaces containing singularities in the form of sharp edges and characterized by three quantum numbers despite the two-dimensional nature of the surface. We explore the nature of the plasmonic excitations, their ability to generate large concentrations of optical energy, and the transition from the discrete excitation spectrum of a non-singular surface to the continuous spectrum of a singular metasurface.