Abstract
Two sodium borosilicate glasses containing Er3+ were isothermally heat treated for phase separation, followed by the formation of the droplet and interconnected textures, respectively. The effects of heat treatment condition and the phase separated texture on photoluminescence (PL) intensity of 4S3/2→4I15/2 transition of Er3+ were studied. It was found that the PL intensity increased with phase separation developing in both glasses. Moreover, the maximum PL intensities obtained by the phase separation in both glasses are 8.5 and 4.1 times as high as those in the respective untreated samples, the droplet texture being superior to the interconnected one. The mechanism of augmentation of the PL intensity was discussed in terms of the derived expression of the PL intensity. It was supposed that the induced interface after phase separation, causing notable increase in the radiative decay rate from the 4S3/2 to 4I15/2 levels, was responsible for the significant enhancement in the PL intensity.
