Radiative damping of surface plasmon resonance in spheroidal metallic nanoparticle embedded in a dielectric medium

TL;DR

This paper investigates how radiative damping of surface plasmons in spheroidal metallic nanoparticles varies with size, shape, and surrounding medium, highlighting quadratic growth and oscillatory behavior, with detailed calculations for gold and sodium.

Contribution

It introduces a detailed theoretical analysis of radiative damping considering particle shape, size, and dielectric environment, including electron surface-scattering effects.

Findings

Radiative damping increases quadratically with particle radius.

Damping oscillates with changes in particle size and dielectric constant.

Electron surface-scattering significantly influences plasmon decay.

Abstract

The local field approach and kinetic equation method is applied to calculate the surface plasmon radiative damping in a spheroidal metal nanoparticle embedded in any dielectric media. The radiative damping of the surface plasmon resonance as a function of the particle radius, shape, dielectric constant of the surrounding medium and the light frequency is studied in detail. It is found that the radiative damping grows quadratically with the particle radius and oscillates with altering both the particle size and the dielectric constant of a surrounding medium. Much attention is paid to the electron surface-scattering contribution to the plasmon decay. All calculations of the radiative damping are illustrated by examples on the Au and Na nanoparticles.