Growth and luminescence properties of Pr-doped LU3(Ga,Al)5O12 single crystals

Single crystals with the nominal composition of (Pr-0.01,Lu-0.99)(3)(Ga-x,Al1-x)(5)O-12 (Pr:LuGAG) were grown by the micro-pulling-down (mu-PD) method with RF heating and their luminescence properties were characterized. Transparent and crack free crystals that were slightly yellowish green were obtained. Lattice constants and densities systematically increased with increasing of Ga concentration. The luminescence properties of Pr:LuGAG were characterized by photoluminescence spectra and decays, radioluminescence spectra and light yield measurements. 5d-4f luminescence was observed for the x <= 0.6 samples. It was found that the 5d-4f emission of Pr3+ is quenched only slightly up to x <= 0.4 whereas density systematically increased in the range of 0 <= x <= 1.0.