Photostimulated luminescence in a rare earth-doped fluorobromozirconate glass ceramic

Photostimulated luminescence at room temperature was observed in a fluorozirconate glass which was doped with 1% ${\mathrm{Eu}}^{\mathrm{2+}}$ or 1% ${\mathrm{Ce}}^{\mathrm{3+}}$ and 5% ${\mathrm{Br}}^{\mathrm{-}}$ ions. Small crystals of ${\mathrm{BaBr}}_{\mathrm{2}}$ (high-pressure phase) form in the glass on cooling. The ${\mathrm{Eu}}^{\mathrm{2+}}$ and ${\mathrm{Ce}}^{\mathrm{3+}}$ luminescence spectra comprised two emission lines each: for ${\mathrm{Eu}}^{\mathrm{2+}}$ one line at 413 nm and a broader band centered at 485 nm, and for ${\mathrm{Ce}}^{\mathrm{3+}}$ one line at 320 nm and a broader band at 425 nm. The luminescence is attributed to the ${\text{5d}}^1{\text{4f}}^{\text{n−1}}{\text{→4f}}^n$ emissions of the rare earth ions. In both cases only one of the emission bands showed photostimulated luminescence. The stimulation band for both rare earth ions was centered at 570 nm.