Numerical simulation of optical dispersion, group velocity, and waveguide properties of gold and silver nanocolloids and hybrids

This work is a numerical study of optical properties of colloids and polymers composed of gold and silver nanoparticles. A numerical method has been used to simulate absorption and dispersion properties of colloids and hybrids composed of gold and silver nanocolloids. For individual nanoparticles, optical susceptibilities and constants are studied considering their limited size effects. A theoretical model is used to relate macroscopic optical behavior of the nanohybrids to the susceptibility of individual particles. Effects of the size and the volume fraction of the particles on the peak and broadening of the absorption and dispersion bands are also discussed. The kind of the solvent in colloids and the host polymer in optical fibers composed of nanoparticles is a key parameter that is investigated. The group velocity of the light propagation in the mentioned hybrids is studied. Subsequently, waveguide properties of optical fibers made of PVA polymer composed of gold and silver nanoparticles are simulated numerically. As the main advantage of this procedure, dispersion and absorption curves of the nanohybrids could be obtained simultaneously. Optical dispersion curves, group velocity curves, and waveguide properties of these nanohybrids are offered for the first time.