Dipole-induced localized plasmon modes and resonant surface plasmon scattering

TL;DR

This paper investigates how a dipole near a metal film can induce localized plasmon modes within the continuum of surface plasmons, leading to resonant scattering that can be controlled by the dipole's position, with implications for nanoplasmonics.

Contribution

It demonstrates the formation of localized plasmon modes induced by a dipole in a metal film and identifies the optimal conditions for resonant scattering.

Findings

Maximum scattering occurs when the dipole is at half the film thickness from the surface.

Localized plasmon modes can exist within the continuum of propagating surface plasmons.

Controllable plasmon scattering has potential applications in nanoplasmonics.

Abstract

A metal film supports the continuum of propagating surface plasmon waves. The interaction of these waves with a dipole (nanoparticle) positioned some distance from the surface of the film can produce well defined localized plasmon modes whose frequency nonetheless resides inside the continuum. This leads to the resonant enhancement of scattering of surface plasmons off the dipole. The maximum of scattering is found to occur when the distance from the dipole to the surface of the film is equal to one half of the film thickness. The possibility of controllable plasmon scattering could be advantageous for the field of nanoplasmonics.