Photostimulated luminescence in Eu2+-doped fluoroaluminate glasses

Photostimulated luminescence phenomenon was observed in a fluoroaluminate glass doped with Eu2+. When the x-ray irradiated glass was excited by a He–Ne laser (633 nm), photostimulated luminescence at 400 nm due to the 5d–4f transition of Eu2+ ions was observed. X-ray absorption spectra showed that a part of Eu2+ converted to Eu3+ upon the irradiation of x-ray. By comparing with the investigations on photostimulable luminescence phosphor BaFBr:Eu2+, the luminescence appears to result from the photostimulated recombination of holes and electrons at traps, which leave electrons in a long-lived excited state.