Laser- and gamma-ray induced crystallization of IR-transmitting calcium gallate glass

Ar+-laser (λ=488 nm) irradiation of calcium gallate (CG) glass with the composition of 60CaO·39Ga2O3·Fe2O3 resulted in a distinct decrease in the IR transmittance (T) due to the formation of crystalline CaGa2O4 and CaGa4O9 phases. The Mossbauer spectrum of non-irradiated glass comprised a broad doublet due to distorted Fe3+(Td) withδ, Δ, andΓ of 0.20, 1.33, and 1.00 mm s−1, respectively. An additional doublet due to Fe3+(Td) was observed in the Ar+-irradiated glass andδ, Δ, andΓ were 0.17, 1.32, and 0.75 mm s−1, respectively. A decrease inT was also observed after the60Co γ-ray irradiation with doses ≥105Gy, and the precipitation of CaO, Ga2O3, and CaGa4O7 phases was confirmed by X-ray diffraction.