Fabrication and characterization of nanoparticle-based plasmonic nanostructures

Small metal nanostructures, especially gold and silver nanoparticles, are known for their interesting optical properties caused by plasmons. Isotropic or anisotropic, homogeneous or heterogeneous metal nanoparticles provide a platform for different highly defined functional units with interesting optical properties for applications such as waveguides or (in combination with molecular parts) molecular beacons. We combined such nanoparticles with sub-wavelengths apertures in metal films, and studied the effect of the presence of particles in these nanocavities on the topography as well as on the optical behavior. Therefore, methods were developed that allow for a correlation of topography and optical properties. The transmission through the holes was clearly influenced by the presence of nanoparticles. Combined with the potential of designing the plasmonic properties of particles by customized diameters as well as composition using core-shell techniques, this approach promises an interesting novel class of plasmonic nanostructures.