Coupling between plasmonic films and nanostructures: from basics to applications

Plasmonic film-nanoparticles coupled systems have had a renewed interest for the past 5 years both for the richness of the provided plasmonic modes and for their high technological potential. Many groups started to investigate the optical properties of film-nanoparticles coupled systems, as to whether the spacer layer thickness is tens of nanometers thick or goes down to a few nanometers or angstroms, even reaching contact. This article reviews the recent breakthroughs in the physical understanding of such coupled systems and the different systems where nanoparticles on top of the spacer layer are either isolated/random or form regular arrays. The potential for applications, especially as perfect absorbers or transmitters is also put into evidence.