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Tuning Dichroic Plasmon Resonance Modes of Gold Nanoparticles in Optical Thin Films


Lola González-García, Julián Parra-Barranco, Juan Ramón Sánchez-Valencia, Javier Ferrer, Mari-Cruz García-Gutiérrez, Ángel Barranco, Agustín R. González-Elipe Advanced Functional Materials 2012, Vol. 23, 1655-1663

A simple method is presented to tune the gold Surface Plasmon Resonance (SPR) modes by growing anisotropic nanoparticles into transparent SiO2 thin films prepared by GLADPVD. In this type of composite film, the anisotropy of the gold nanoparticles, proved by different techniques as Gracing Incidence Small Angle X-ray Scattering (GISAXS), Scanning Electron Microscopy (SEM) and UV-Vis spectroscopy, is determined by the tilted nanocolumnar structure of the SiO2 host and yields a strong film dichroism evidenced by a change from an intense colored to a nearly transparent aspect depending on light polarization and/or sample orientation. The formation in these films of lithographic non-dichroic SPR patterns by nanosecond laser writing demonstrates the potentialities of this procedure to develop novel optical encryption or anti-counterfeiting structures either at micrometer- or macroscales.