Silver (Ag<sup>+</sup>) doped phosphate glass exhibits an intense photoluminescence (PL) when the non-irradiated Ag<sup>+</sup>-doped
phosphate glass is excited with about 230 nm ultra-violet light. In x-ray irradiated glass, intense
radiophotoluminescense (RPL) is observed when the irradiated glass is excited with about 340 nm ultra-violet light. It
is found that the RPL spectrum includes two emission bands such as blue emission band peaked at about 460 nm
(lifetime: about 6.6 ns) and yellow RPL emission band peaked at about 560 nm (lifetime : about 2.2μs). The PL
intensity is decreased with increasing x-ray irradiation dose, while the RPL intensity is increased with x-ray absorbed
dose. For the annealing of x-ray irradiated glass at 523 K, the RPL intensity is decreased with annealing, while the PL
intensity is increased with annealing. The RPL is vanished and the PL is recovered at original intensity by annealing at
523 K for 40 min. This means that there is a complementary relationship between the PL and RPL on irradiation and
heat-treatment processes. The RPL intensity is increased with increasing the x-ray absorbed dose in the range from
0.01 mGy to about 20 Gy, showing that the Ag<sup>+</sup>-doped phosphate glass can be useful for individual radiation monitoring
and environmental radiation monitoring. On the basis of such potentiality of glass as the dosimeter, the application of
Ag<sup>+</sup>-doped phosphate glass on environmental radiation monitoring is discussed and the RPL response of the glass for α-
particle and heavy-particle (He, C, Fe particle) irradiation is demonstrated.
Focused infrared femtosecond laser pulses (wavelength ~800 nm, emission pulse duration 100 fs) were employed to
fabricate optoelectronic devices such as waveguides, micro-gratings and laser active centers in LiF crystals. F<sub>2</sub> color
centers of about 2x10<sup>18</sup> cm<sup>-3</sup> and refractive index change of about 1% at 633 nm were induced by the fs-laser irradiation.
This technique was applied to fabricate a distributed-feedback (DFB) F<sub>2</sub> color center laser structure inside LiF single
crystal. The LiF DFB laser exhibited laser oscillation at 707 nm at room temperature. The slope efficiency of ~10% and
beam divergence of ~20 mrad were achieved.