Development of Composite Scintillators Based on Single Crystalline Films and Crystals of Ce3+-Doped (Lu,Gd)3(Al,Ga)5O12 Mixed Garnet Compounds

The possibility of growth by the liquid phase epitaxy method of a new type of advanced composite scintillator based on Ce 3+ -doped single crystalline films (SCFs) of Lu 1.5 Gd 1.5 Al 1.5 Ga 3.5 O 12 garnet and substrates from single crystals (SCs) of Gd 3 Al 2.5 Ga 2.5 O 12:Ce garnet is evidenced for the first time in this work. We show the possibility of the simultaneous registration of α-particles and γ-quanta by way of separation of the scintillation pulse height spectra and decay kinetics of SCF and crystal parts of such a composite scintillator. Namely, the significant differences in the scintillation decay kinetics of Lu 1.5 Gd 1.5 Al 1.5 Ga 3.5 O 12:Ce SCF/Gd 3 Al 2.5 Ga 2.5 O 12:Ce SC composite scintillator under excitation by α-particles of a 241 Am (5.5 MeV) source and γ-quanta of 137 Cs (662 keV) source are observed. The respective t α/ t γ decay times ratio in the 0–500 ns range reach up to 0.5 for this type of composite scintillator; e.g., the SCF scintillators is two times faster than the substrate scintillator. For this reason, such a type of composite scintillator can be successfully applied for the separation of the signals coming from its film and crystal parts at the registration of the mixed radiation fluxes of α-particles and γ-quanta.