Analysis of plasmon oscillations in metallic nanoparticles

Abstract

Purpose

To study optical resonances in metallic nanoparticles.

Design/methodology/approach

The metallic nanoparticle is modeled as a dielectric body dispersive in frequency with assigned dielectric constant. The electric field is expressed as function of the charge distribution through an integral formulation. By imposing the boundary conditions on the nanoparticle surface, the equations for the induced charge in the nanoparticle is obtained. The numerical solution of such equations allows to treat arbitrary geometries and to estimate the effects of deviations from ideality on the resonance values.

Findings

Plasmon resonances in metallic nanoparticles can be safely studied with an electro‐quasistatic approximation. The resonance frequencies depend greatly on the details of the geometry of the nanoparticles.

Research limitations/implications

The free‐space wavelength is supposed to be much greater than the largest characteristic dimension of the nanoparticles. Consequently, a electro‐quasistatic model is used to evaluate the distribution of the charges induced in the metallic nanoparticle.

Originality/value

Two methods are presented for the evaluation of the resonance frequencies starting from the numerical solution for a given geometry.

Citation

Miano, G., Villone, F. and Zamboni, W. (2007), "Analysis of plasmon oscillations in metallic nanoparticles", COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, Vol. 26 No. 3, pp. 626-639. https://doi.org/10.1108/03321640710751109