The plasmon resonance of metallic Au/Ag alloys in the colloidal state wastuned from 400 nm to 500 nm using a laser irradiated technique, performed directly in theliquid state. Interesting optical nonlinearities, trapping effects and spectroscopic enhancementswere detected as function of gold concentration in the nanoalloys. In particular areduction of the limiting threshold was observed by increasing the gold amount. The SERSactivity of the Au/Ag alloys was tested in liquid and in solid state in presence of linear carbonchains as probe molecules. The dependence of the increased Raman signals on thenanoparticle Au/Ag atomic ratio is presented and discussed. Finally preliminary studiesand prospects for optical and Raman tweezers experiments are discussed.
TUNING THE STRUCTURAL AND OPTICAL PROPERTIES OF GOLD/SILVER NANOALLOYS PREPARED BY LASER ABLATION IN LIQUIDS FOR ULTRA-SENSITIVE SPECTROSCOPY AND OPTICAL TRAPPING
D'URSO, LUISA;SATRIANO, Cristina;COMPAGNINI, Giuseppe Romano;
2011-01-01
Abstract
The plasmon resonance of metallic Au/Ag alloys in the colloidal state wastuned from 400 nm to 500 nm using a laser irradiated technique, performed directly in theliquid state. Interesting optical nonlinearities, trapping effects and spectroscopic enhancementswere detected as function of gold concentration in the nanoalloys. In particular areduction of the limiting threshold was observed by increasing the gold amount. The SERSactivity of the Au/Ag alloys was tested in liquid and in solid state in presence of linear carbonchains as probe molecules. The dependence of the increased Raman signals on thenanoparticle Au/Ag atomic ratio is presented and discussed. Finally preliminary studiesand prospects for optical and Raman tweezers experiments are discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
