Nanostructured metal-dielectric interfaces for photonic applications

Nanostructured interfaces between noble metals and organic semiconductors are described, with particular attention to novel devices exhibiting a photonic bandgap for propagating surface plasmons. These devices can take advantage both of the outstanding nonlinear properties of photonic molecules, such as polydiacetylenes, and of the localization effects associated with the excitation of propagating or localized surface plasmons, that characterize metal surfaces with random or regular nanostructuring. Moreover, it is shown how a suitable nanostructuring of the metal-dielectric interface can be conveniently exploited for enhancing or tuning the chemico-physical properties of molecular adsorbates (i.e. optical nonlinearity, conformation, degree of polymerization)