Thermal annealing and laser induced structural rearrangement and silver state modification in Ag+-Na+ ion-exchanged silicate glasses studied by Raman spectroscopy

The structural modification of the host matrix induced by external treatments in ion-exchanged silicate glasses have not been studied rigorously, despite its importance in tailoring the performances of optical devices. Silicate glass layers prepared by Ag+-Na+ ion-exchange were annealed and irradiated with laser beam. The rearrangement of silica network and Ag clustering process during external treatments in silver-containing glasses were studied by Raman spectroscopy. Modifications of silica network microstructure in ion-exchanged and treated glasses were investigated by analyzing Raman band in between 700 and 1250 cm(-1). External treatments result in the sequence of structural changes, which may be interpreted as the change in polymerizing units, appearance and disappearance of non-bridging oxygen centers in glass. The transformation of silver during external treatments was evidenced from the low-frequency Raman spectra. A final assignment of silica-network microstructure modifications due to cluster fragmentation with high energy laser irradiation is attained by using Raman spectral analyses.