Plasmonics and near field optics for sensing purposes

In the first part of the thesis I present a theoretical and experimental work due to develop a performing configuration for gas-sensing through the employ of Surface Plasmon Resonance effect. Different sensing layers have been studied and tested on our optical bench assembly. Metallic (Au) and bimetallic (Ag/Au) layers have been properly designed through simulations and then have been realized through electron-beam evaporation. TiO2 and TiO2 - Au doped layers have been deposited on the top of some of the metallic samples. These layers were prepared by the sol gel route. In the second part I focused on the development of an experimental set-up able to study the local field at an interface between two dielectrics. An approach based on photo-thermal-deflection has been used. Chromophores have been used as probes of the local field

Nella prima parte della mia tesi presento un lavoro teorico e sperimentale atto a sviluppare una configurazione adatta alla sensoristica, sfruttando il fenomeno della risonanza plasmonica di superficie. Diferse configurazioni dello strato sensibile sono state testate sul set-up da banco ottico, costruito a tale scopo. Nella seconda parte mi sono concentrata sullo sviluppo di un metodo sperimentale per lo studio del campo elettrico all'interfaccia tra due dielettrici. Si è usato un approccio basato su photo-thermal-deflection. Come sonde del campo locale sono state utilizzate delle molecole cromofore