Photo- and X-ray excited luminescence, thermoluminescence and scintillation characteristics of LuGd2Al3Ga2O12:Ce,Mo single crystal scintillators: Influence of Mo co-doping

Mo co-doped LuGd2Al3Ga2O12:Ce,Mo (Mo =0, 300, 600 ppm) single crystals were grown by the micro-pulling- down method. The optical absorption and X-ray excited luminescence spectra, temperature dependence of photoluminescence decay kinetics, afterglow and thermoluminescence (TL) intensity, and scintillation properties (light yield, LY, and decay time) were investigated. The quenching temperature of 355 K was determined from temperature-dependent photoluminescence decay kinetics in the temperature range of 77–487 K under excita tion in the 4f - 5d1 absorption band of the Ce3+ions. Under excitation of 662 keV γ rays, the LuGd2Al3Ga2O12:Ce, Mo600 sample showed high LY value of 32,900 photons/MeV, energy resolution of 7.6 %, and scintillation decay time of 119 ns (38 %) +475 ns (62 %). The lower LY value together with higher contribution of slower scin tillation decay component among the samples studied was observed for LuGd2Al3Ga2O12:Ce,Mo300 sample, consistently with its higher afterglow intensity and longer de-trapping time of the dominant TL glow peak at 356 K.