Growth of highly concentrated silver nanoparticles and nanoholes in silver-exchanged glass by ultraviolet continuous wave laser exposure

Glasses embedded with silver nanoparticles (NPs) have attractive properties because their optical properties can be adjusted by varying the size, shape, and packing density of the particles. Pulsed laser processing of such composite glasses is a promising approach in glass engineering. In this study, the growth of silver NPs in silver-exchanged soda-lime glasses by ultraviolet (UV) continuous wave (cw) laser irradiation is demonstrated. Highly concentrated NPs of large diameters (roughly 100 nm) are spread over several micrometers near the exposed area. Bleaching of these NPs is observed in the case of intense exposure and results in the imprints of the glass surface with nanoholes, together with the concomitant formation of ripples of a 150 nm period, at the edge of the laser spot. Therefore, cw UV laser processing of silver-exchanged glass leads to the growth of large NPs, unlike more commonly used pulsed lasers, and allows for the periodical patterning of the glass surface with ripples and nanoholes. (C) 2012 Optical Society of America