plasmous
PLASmonic Metasurfaces for Optical Ultrafast Sensors PLASMOUS
B. Palpant, LuMIn, C. Hamon, LPS, CNRS
Abstract
Gold-silver core-shell cuboidal nanoparticles (NPs) exhibit transverse plasmon resonance modes that can open exciting outlooks for applications in the near-ultraviolet range. When shined with ultrashort laser pulses, they show robust and sharp temporal and spectral variation in their transient optical response. In addition, their vibrational landscape features complex acoustic modes. All these characteristics are highly dependent on the surface load of the NPs, which make them promising for sensing. Furthermore, the spatial periodic ordering of NPs into tight supercrystals modulate and amplify the plasmon modes.
In PLASMOUS, we will synthesize plasmonic metasurfaces made of 2D superlattices of vertically-standing Au-Ag nanoparticles for a further exploitation in molecular sensing. Gold nanorods will be synthesized and coated with a silver shell with varying thickness. They will be stacked into 2D periodic arrays by evaporation-induced self-assembly. The superlattices will be modulated from hexagonal- to square-type. They will be characterized by electron microscopies. Their optical response will be measured and analyzed by a proper modelling, in the stationary and transient regimes. Their potential for optical sensing will be later explored and optimized, based on their ultrafast transient optical response.