Scintillation and Luminescent Properties of Cerium Doped Lutetium Aluminum Garnet (Ce:LuAG) Powders and Transparent Ceramics

Transparent cerium doped lutetium aluminum garnet (Ce:LuAG) ceramic scintillantors with different Ce3+ concentrations were densified successfully from synthetical nanosized Ce: LuAG powders using co-precipitation method. It was found that the 0.5 mol% Ce: LuAG ceramic exhibited the highest luminescent emission intensity under synchrotron radiation excitation which could be divided into two components centered at 505 and 540 nm under low temperature (50-150 K) conditions originated from the 5d(1) excited level (D-1) to the 4f ground state of Ce3+ (F-2(5/2);F-2(7/2)). The quantum efficiency (QE) of the optimized Ce: LuAG ceramic could reach 66.3% under UV excitation of 345 nm. Typical absorption at 170 nm related to possible Lu-Al(3+) antisite defect (AD) was observed both in Ce3+ doped and un-doped LuAG ceramics which formed electron traps disturbing the energy transfer from host lattice to Ce3+ centers, leading to a slow decay component of 109.4 ns in the 0.5 mol% Ce: LuAG transparent ceramic under Cs-137 (662 keV) irradiation.