Growth, structure and radiation resistant properties of Er,Pr:GSAG laser crystals

Er, Pr co-doped GSAG laser crystal with high optical quality was successfully grown by the Czochralski method for the first time. X-ray rocking curve exhibit the high crystalline quality of this crystal. The intensities of optical transmission and luminescence of Er,Pr:GSAG crystal were not deteriorate after the gamma-ray irradiation even with a dose of 1.16 × 106 Gy, confirming the excellence radiation resistant property of Er, Pr:GSAG crystals. The efficiencies of energy transfer from 4I11/2 to 1G4 and 4I13/2 to 3F4 between Er3+ and Pr3+ ions in GSAG crystal are determined as 16.7% and 94.9%, which indicate that the Pr3+ can act as an deactivator ions for Er3+ ions in Er,Pr:GSAG crystal. Additionally, the luminescence spectra of Er,Pr:GSAG crystal are compared with that of Er:GSAG crystal in the visible and near-IR regions, which provided that Pr3+ ions can efficiently depopulate the 4I13/2 level and reduce the fluorescence lifetime. All the results demonstrate that Er,Pr:GSAG crystal can realize multi-wavelength laser output at 2.6-2.9 μm under harsh radiation environment.