The role of morphology and coupling of gold nanoparticles in optical breakdown during picosecond pulse exposures.

This paper presents a theoretical study of the interaction of a 6 ps laser pulse with uncoupled and plasmon-coupled gold nanoparticles. We show how the one-dimensional assembly of particles affects the optical breakdown threshold of its surroundings. For this purpose we used a fully coupled electromagnetic, thermodynamic and plasma dynamics model for a laser pulse interaction with gold nanospheres, nanorods and assemblies, which was solved using the finite element method.

A quantitative study of the environmental effects on the optical response of gold nanorods.

The effects of the dielectric environment on the optical extinction spectra of gold nanorods were quantitatively studied using individual bare and silica-coated nanorods. The dispersion and amplitude of their extinction cross-section, dominated by absorption for the investigated sizes, were measured using spatial modulation spectroscopy (SMS). The experimental results were compared to calculations from a numerical model that included environmental features present in the measurements and the morphology and size of the corresponding nanorods measured by transmission electron microscopy.