Optical studies on X and γ irradiated vacuum grown CsBrI:Eu2+ crystals

Abstract CsBr 0.9 I 0.1 :Eu 2+ crystals were grown by Bridgman technique. Optical absorption spectrum of the unirradiated CsBr 0.9 I 0.1 :Eu 2+ crystals show absorption bands at 270 nm and 340 nm. Irradiated CsBr 0.9 I 0.1 :Eu 2+ shows single F band for F(Br − ) and F(I − ) centers at 730 nm. Conversion of Eu 2+ to Eu 3+ after irradiation is confirmed by optical absorption technique. Sharp and single Photoluminescence (PL) emission band is observed at 440 nm for CsBr 0.9 I 0.1 :Eu 2+ crystals. Photostimulated Luminescence (PSL) emission band observed for CsBr 0.9 I 0.1 :Eu 2+ crystals at 442 nm due to excitation at 730 nm shows that the F centers are photostimulable. PSL emission intensity increases linearly with irradiation dose up to 2.5 Krad.