We propose a new method to strudy photothermal effect in large arrays of coupled plasmonic nanoparticles based on monitoring of surface acoustic waves propagating in LiNbO3 substrate. A photothermal effect induced by deposited nanosystem/metasurface results in SAW velocity alteration which a phase shift is detected. In proof-of-concept experiment the visible/near IR polarization/wavelength dependent photothermal responses of macroscopic monolayer of Au plasmonic coupled nanoparticles prepared by self-assembling and the one for larger isolated particles produced by heat treatment were characterized.
We study the surface enhanced Raman scattering of Methylene Blue (MB) dye molecules induced by large quasihomogeneous arrays of plasmon coupled 5-8 nm Au nanoparticle separated by distances less than 10 nm. Also, the variation of the fluorescence enhancement/SERS properties for as-prepared coupled particles and agglomerated particles obtained upon heat treatment and percolation-like films is analyzed for two measurement protocols, i.e. when measured through the solution and for a monolayer of MB molecules chemisorbed on a surface.
We study an ability of a large quasi-homogeneous monolayer of Au plasmon coupled nanoparticles separated from continuous Au film by polymer spacer to enhance a fluorescence of adsorbed molecular species. A fluorescence response of Methylene Blue molecules is studied as a function of polymer film thickness. A change of plasmonic properties of a system, its ability to enhance a fluorescence and the possible heating of a structure upon light absorption are discussed.