Evaluation of effective medium theories for spherical nano-shells

TL;DR

This paper reviews current effective medium theories for nano-shells and introduces a new method that incorporates radiating effects and Mie scattering to improve accuracy in calculating dielectric functions, aiding in designing plasmonic and composite materials.

Contribution

A novel method for calculating the effective dielectric function of core-shell nanoparticles that outperforms existing theories by including radiating effects and exact polarizability calculations.

Findings

The new method shows clear advantages over existing theories in most conditions.

It effectively predicts plasmonic properties of coated particles.

It can be used to engineer composite materials for photocatalysis and solar energy.

Abstract

Current effective medium theories for nano-shells are reviewed. A new method for calculating the effective dielectric function of a core-shell nanoparticle is presented and compared with existing theories showing clear advantages in most conditions. It consists of introducing radiating effects in the polariz- ability of the effective sphere, and considering the exact polarizability of the core-shell constructed from the Mie scattering coefficient. This new approach can be considered as an useful tool for designing coated particles with desired plasmonic properties and engineering the effective permittivity of composites with core-shell type inclusions which are used in photocatalysis and solar energy harvesting applications.