Correlation between paramagnetic and optical measurements on silver-activated phosphate glasses

By irradiation of silver activated phosphate glasses there are different centers formed giving rise to optical absorption, ESR and fluroescence (RPL). On the latter phenomenon an established dosimetry technique is based. For its improvement, a better understanding of the physical fundamentals is of interest, particularly on the kind of the dosimetric relevant RPL centers. We tried to get such information on the center structure by correlating the significant signals of the ESR, RPL and optical density spectra. The investigations mainly concerned the changes in the above spectroscopic signals due to isothermal and isochronic annealing. Varying parameters have been the silver concentration and the dose levels to which the glasses have been exposed. As a result, new data have been found on the RPL mechanism, partly in disagreement with the present state of knowledge. In general, silver turned out to be necessary for the generation of a RPL center, but not sufficient. It could be shown, that not all radiation induced silver centers contribute to luminescence. The ratio between the luminescent and non-luminescent centers related to silver depends on the magnitude of dose applied and on the silver concentration. The two emission bands present in a typical RPL spectrum could not be attributed to simple paramagnetic silver centers formed by irradiation. (author)