Modeling the optical properties of nanocluster-based functional plasmonic materials

Optical properties of nanocluster-based plasmonic materials were studied along this thesis by the Generalized Multiparticle Mie approach. Far- and local-field optical properties of basic plasmonic structures such as sphere dimers and chains were successfully analyzed as a function of their composition and their topological features. The provided physical insight is then exploited in the modeling of strongly coupled complex structures obtained by ion beam processing. These systems were called nanoplanets since they are constituted by a large central cluster surrounded by small satellite ones very close to its surface. Nanoplanets show extremely interesting far- and local-field properties which may be carefully tailored by varying the ion beam synthesis conditions. GMM theory allowed to establish that the strong interparticle coupling is at the base of their peculiar optical features. Finally multiple coupled cluster are proposed as efficient nanoantennae. Nanoparticle dimers were proved to provide extremely efficient broadband light extraction. If regular sphere array are used instead, broadband limitation imposed by isolated antennae may be overcome and tunable wavelength selective recombination rate enhancement is obtained. Overall this thesis gives an interesting insight in the plasmonic properties of functional multiple coupled cluster nanostructures.