Three-layered composite scintillator based on the epitaxial structures of YAG and LuAG garnets doped with Ce3+ and Sc3+ impurities

In this work, we have proposed new types of three layered composite scintillators for simultaneous registration of the different components of ionization radiation based on the epitaxial structures of LuAG and YAG garnets, doped with Ce3+ and Sc3+ ions. The samples of such composite scintillators, containing YAG:Ce and LuAG:Ce single crystalline films with different thicknesses and LuAG:Sc single crystal substrates were grown using the Liquid Phase Epitaxy method from melt-solutions based on PbO-B2O3 fluxes. The scintillation properties of proposed composites YAG:Ce film/LuAG:Sc film/LuAG:Ce crystal and YAG:Ce film/LuAG:Ce film/LuAG:Sc crystal were investigated under excitation by radiation of α–particles of 239Pu source; b-particles of 90Sr sources and γ-rays of 137Cs source. Considering the properties of the mentioned composite scintillators, special attention was paid to the ability of simultaneous separation of the different components of mixed ionizing radiation containing mentioned particles and quanta using scintillation decay kinetics. The differences in the scintillation decay curves under α– and b- particle and γ-rays excitations were characterized by the Figure-of-Merit (FOM) values at different scintillation decay intensity levels (1/e, 0.1, 0.05, 0.01).