Luminescent centers formation and non-linear optical effects in photo-thermo-refractive glass under femtosecond IR laser pulses
ITMO University, Russian Federation
Our work is devoted to the investigation of optical, mainly luminescent properties of silver-containing glass. We used a femtosecond laser for the irradiation of samples. The experiments have shown that the initial glass has weak luminescence, but during irradiation by the femtosecond laser a multiphoton ionization of glass components occurs and forms free electrons in the glass. They are trapped by Ag+ ions and Agn+ molecular clusters and are converted in to neutral Ag0 and Agn0 clusters. In result the obtained clusters have strong luminescence intensity in spectral range of 480-800 nm. The glass have non-linear properties that result into complex propagation of laser beam through the glass. In contrast with another ways of silver molecular clusters a luminescence of irradiated region remains after the thermal treatment at the temperature above Tg.