Optical and transport properties of spheroidal metal nanoparticles with account for the surface effect

TL;DR

This paper develops a kinetic model to analyze the optical and transport properties of spheroidal metallic nanoparticles, considering surface effects and shape anisotropy, revealing size and frequency-dependent dielectric and conductivity behaviors.

Contribution

It introduces a kinetic approach to extend the Drude-Sommerfeld model for spheroidal nanoparticles, accounting for surface effects and shape anisotropy.

Findings

Dielectric function and conductivity depend on size, shape, frequency, and orientation.

Oscillations in dielectric properties occur with size increase or frequency change.

Kinetic model results are compared with classical models, showing differences.

Abstract

The kinetic approach is applied to develop the Drude-Sommerfeld model for studying of the optical and electrical transport properties of spheroidal metallic nanoparticles, when the free electron path is much greater than the particle size. For the nanoparticles of an oblate or a prolate spheroidal shape there has been found the dependence of the dielectric function and the electric conductivity on a number of factors, including the frequency, the particle radius, the spheroidal aspect ratio and the orientation of the electric field with respect to the particle axes. The oscillations of the real and imaginary parts of the dielectric permeability have been found with increasing of particle size at some fixed frequencies or with frequency increasing at some fixed radius of a nanoparticle. The results obtained in kinetic approach are compared with the known from the classical model.