All optical formation and decomposition of silver nanoparticles in glass

Abstract

The process of laser radiation-induced formation and decomposition of Ag nanoparticles in glass is studied. Borosilicate glass samples are fabricated by melt quenching method. Silver nitrate is added in the fabrication stage in amount to form final glass samples with compositions of 1, 1.5, 5, and 10 wt% Ag. The fabricated samples are irradiated by laser pulses delivered by Nd:YAG nanosecond laser system at wavelength of 266 nm. It is found that at certain conditions laser radiation can induce coloration of the irradiated zone which is related to formation of silver nanoparticles. Detailed analyses are performed to characterize the formed nanoparticles. The application of a subsequent laser treatment of the glass samples with already formed nanoparticles can result in transparency recovery. The effect is demonstrated at wavelength of 355 nm of the Nd:YAG laser system. The observed formation and decomposition of nanoparticles are discussed on the basis of the calculated laser-induced heating dynamics and molecular dynamics simulation model for the silver atom motion. Diffusion growth and redox reactions are found to be responsible for the observed effects.