Radiophotoluminescence properties of Ag-doped phosphate glasses

The radiophotoluminescence (RPL) of Ag-doped phosphate glass has been used for personal dosimetry for a long time. In this study, we investigated the optical properties of Ag-doped various phosphate glasses. It is revealed that alkali metals in the phosphate are required to achieve the RPL, and that the alkali metals content has an influence on the RPL properties. Also, the ESR signal corresponding to the valence change of Ag was observed only for the phosphate glasses containing alkali metals. These results indicate that the RPL occurs based on the change in Ag valence state, which is consistent with commercial phosphate glasses used for dosimetry. In addition, the decay-time constants of the RPL were on the order of microseconds. Furthermore, initialization of the RPL was observed after heating at 473 K, which indicates that these glasses can be used repeatedly.