Femtosecond-laser-activated fluorescence from silver oxide nanoparticles

Abstract

A method for fast spatially resolved photoactivation of fluorescence from silver oxide nanoparticle films is presented. High activation rates are achieved through fast scanning of a focused high repetition rate 800 nm femtosecond laser with a peak power of 6.5 MW/cm2 over the sample. The activated areas of the thin films show fluorescence after subsequent excitation with an Ar+/Kr+ laser. The fluorescent properties were investigated by means of scanning laser microscopy at ambient conditions. Depending on excitation wavelengths (488 or 568 nm) strong fluorescence in the green or red domain was observed. The activation efficiencies were examined both as a function of exposure time and femtosecond laser power. Sensitivity, reliability and possible mechanisms for the photoactivation process are discussed.