Self-assembled plasmonic nanoparticle clusters

Optical Nanoengineering Optics and electronics operate at very different length scales. Surface plasmons are light-induced electronic excitations that are being pursued as a route to bridge the length scales and bring the processing speed offered by optical communication down to the size scales of electronic chip circuitry. Now, Fan et al. (p. 1135 ) describe the self-assembly of nanoscale dielectric particles coated with gold. Functionalization of the gold surface with polymer ligands allowed controlled production of clusters of nanoparticles. The optical properties of the self-assembled nanostructures depended on the number of components within the cluster and each structure could be selected for its unique optical properties. Such a bottom-up approach should help in fabricating designed optical circuits on the nanoscale.