Plasmonics for the industry

摘要

Metallic nanostructures interact strongly with light through surface plasmon modes and many application fields have been proposed during the past decade, including light harvesting, sensing and structural colors. However, their implementation for the industry requires the development of up scalable and cost effective manufacturing processes. The fabrication at wafer scale of plasmonic nanostructures and metamaterials using nano imprint lithography is reported. After structuring, the evaporation of various plasmonic materials are performed with a tilt angle with respect to the substrate, which increases the light interactions with the different metallic layers as well as enlarges the design possibilities. A step and repeat process is used to increase further the area of nanos-tructured surface. The measured optical properties of the fabricated structures show a very good agreement compared to numerical calculations using the rigorous coupled wave analysis. These numerical calculations together which structural characterization, increase the process control and enable the design of the nanostructures for specific applications. In particular, nanostructures with a shape similar to split ring resonators and which support high order plasmonic modes showing Fano resonances are shown to be promising for sensing applications. The structures were designed in such a way to have a strong spectral response in the blue/green region of the visible spectrum. Examples of refractive index sensors and stretch sensors were finally discussed.