Impact of interparticle dipole-dipole interactions on optical nonlinearity of nanocomposites

TL;DR

This paper investigates how dipole-dipole interactions among semiconductor nanoparticles influence their nonlinear optical properties, providing analytical models applicable across various concentrations and configurations.

Contribution

It introduces analytical expressions for dipole-dipole coupling effects on nonlinear susceptibility in nanocomposites, covering the full volume fraction range and different dipole arrangements.

Findings

Dipole-dipole interactions significantly affect nonlinear optical response.

The contribution varies by at most one-third across configurations.

Models are applicable for all nanoparticle volume fractions.

Abstract

In this paper, effect of dipole-dipole interactions on nonlinear optical properties of the system of randomly located semiconductor nanoparticles embedded in bulk dielectric matrix is investigated. This effect results from the nonzero variance of the net dipole field in an ensemble. The analytical expressions describing the contribution of the dipole-dipole coupling to nonlinear dielectric susceptibility are obtained. The derived relationships are applicable over the full range of nanoparticle volume fractions. The factors entering into the contribution and depending on configuration of the dipoles are calculated for several cases. It is shown that for the different arrangements of dipole alignments the relative change of this contribution does not exceed 1/3.