Precise localization and correlation of single nanoparticle optical responses and morphology

We demonstrate nanometer scale localization of the nonlinear optical response of single nanoparticles and aggregates and correlate this with their morphology. The essence of our approach is to create position markers on an optical and electron-transparent substrate (Si3N4 thin film) that allows optical measurements and transmission electron microscopy (TEM) imaging of the identical nanoparticles or aggregates. The second harmonic activity optical image of individual Ag nanostructures is registered with the TEM image. Centroid localization of the optical signals allows correlation with better than 25nm precision. This is sufficient to determine the origin of optical “hot spots” within multiparticle aggregates.