Characterizations of Ce-doped Y_4Al_2O_9 Crystals for Scintillator Applications

摘要

Ce-doped Y4Al2O9 (YAM) crystals were grown by the floating zone method, and several different characterizations were conducted for scintillator applications. Both photoluminescence (PL) and scintillation show emissions predominantly due to the 5d-4f transitions of Ce3+ over 400-600 nm. The luminescence lifetime is approximately 10 ns for PL while the scintillation decay curve is best fitted by a second-order exponential decay function with the lifetimes of approximately 30 and 300 ns. These lifetimes are faster than that for Ce:Y3Al5O12 (YAG) (similar to 120 ns) and close to that of Ce:YAlO3 (YAP) (similar to 30 ns). The Ce-doped YAM shows a relatively high afterglow signal induced by X-rays (2 ms pulse) possibly due to the inclusion of a large number of defect centers. Pulse height spectroscopy was demonstrated under alpha-ray irradiation, and a successful sample showed a full-energy peak.