Effects of Sc3+ admixture on luminescence and scintillation properties of Ce3+-doped Lu2Y(Al5-xScx)O12 (x = 1, 1.5, 2) garnet single-crystalline films
Abstract
Effects of Sc(3+) admixture on luminescence and scintillation properties were studied in Ce(3+) - doped Lu(2)Y(Al(5-x)Sc(x))O(12) (x = 1, 1.5, 2) garnet single-crystalline films grown by the isothermal liquid phase epitaxy technique. The Ce(3+) photoluminescence (PL) was slightly blue shifted with increasing Sc content due to a decrease in crystal field splitting of the Ce(3+) 5d levels.
In addition, the thermal activation energy of PL quenching, estimated from the temperature dependence of PL decay times, decreased with increasing Sc content. Lu(2)YAl(4)ScO(12):Ce exhibited the highest light yield (LY) value of 420 photons/MeV at 5.5 MeV α particles along with a fast scintillation decay time constant (τ(e)) of 17.4 ns.
At room temperature, the decrease of LY value with increasing Sc content could be attributed to the thermal ionization process.