Photoluminescence of Individual Au/CdSe Nanocrystal Complexes with Variable Interparticle Distances

We investigate the photoluminescence behavior of individual CdSe nanocrystals attached to silica-coated Au nanoparticles. These hybrid nanostructures show enhanced photoluminescence intensity, suppressed off-states, as well as shorter lifetimes in comparison with the isolated CdSe nanocrystals. The very same investigated hybrid nanostructures are further relocated by transmission electron microscopy to study the corresponding structures and geometries. Correlating the optical and structural properties of the hybrid nanostructures, we find that the lifetime shortening of the CdSe nanocrystals depends on the distance between the CdSe nanocrystals and the Au nanoparticles. The results are compared with theoretical calculations based on the FDTD method and the Gersten–Nitzan model.