Retrieving nonlinear refractive index of nanocomposites using finite-difference time-domain simulations

TL;DR

This paper introduces a simulation-based method using 3D FDTD to accurately determine the nonlinear refractive index of nanocomposites by analyzing phase shifts related to input irradiance.

Contribution

It presents a novel approach combining FDTD simulations with phase shift analysis to retrieve the nonlinear refractive index of nanocomposite materials.

Findings

Reconstructed nonlinear refractive index agrees with effective medium theory

Method effectively captures Kerr nonlinearity in nanocomposites

Simulation approach provides accurate nonlinear optical property estimation

Abstract

In this Letter, it is proposed a method which utilizes three-dimensional finite-difference time-domain (FDTD) simulations of light propagation for restoring the effective Kerr nonlinearity of nanocomposite media. In this approach, a dependence of the phase shift of the transmitted light on the input irradiance is exploited. The reconstructed values of the real parts of the nonlinear refractive index of a structure of randomly arranged spheres are in good agreement with the predictions of the effective medium approximations.