Crystal Growth of Ce Doped $({\rm Lu},{\rm Y})_{3}({\rm Ga},{\rm Al})_{5} {\rm O}_{12}$ Single Crystal by the Micro-Puling-Down Method and Their Scintillation Properties

Ce:(Lu,Y)
₃
(Ga,Al)
₅
O
₁₂
single crystals were grown by the μ -PD method with RF heating system. In these crystals, Ce
³⁺
4f-5d emission is observed within 500-530 nm wavelength. Emission peak shifts to shorter wavelength and the decay accelerates with increasing Ga concentration. In the case of Ce:Lu
₂
Y
₁
(Ga,Al)
₅
O
₁₂
series,the Ce0.2% Lu
₂
Y
₁
Ga
₃
Al
₂
O
₁₂
crystal showed the highest emission intensity. In order to determine light yield, the energy spectra were measured under 662 keV ã-ray excitation (
¹³⁷
Cs source) and detection by an APD S8664-55(Hamamatsu). The light yield was calibrated from
Fe
⁵⁵
direct irradiation peak to APD. The light yield of Ce0.2%: Lu
₂
Y
₁
Ga
₃
Al
₂
O
₁₂
sample was of about 30,000 photon/MeV. Dominant scintillation decay time was of about 50 ns.