Search

This work presents the results on creation of novel types of composite scintillators based on Ce3+ doped Gd3Al5-xGaxO12 single crystalline films grown by the LPE method using PbO–B2O3 flux onto substrate-scintillators prepared from commercial Gd3Al2.3Ga2.7O12:Ce and Gd3Al2Ga3O12:Ce single crystals. The sets of films with different Ga contents x = 1.75–2.25 and various thicknesses in the 13–150 μm range were grown onto the mentioned substrates. The scintillation properties of the respective epitaxial structures (pulse height spectra, light yield and scintillation decay kinetics) were investigated under excitation by α– (239Pu) particles, β- (90Sr+90Y) particles and γ–quanta (137Cs). The best scintillation properties for simultaneous registration of the mentioned particles and quanta in the mixed radiation fluxes are demonstrated with Gd3Al2.75Ga2.25O12 film/Gd3Al2Ga3O12:Ce substrate epitaxial structure.

After the discovery of a cross-luminescence (CL) in BaF2 in 1982, a large number of CL scintillators were investigated. However, no CL scintillator superior to BaF2 has been discovered, and the research of CL scintillators has subsided. Recent technological development in medical imaging and high-energy physics created a new demand for ultra-fast scintillators further supported by the development of UV-sensitive semiconductor photodetectors. As a consequence, renewed interest in CL scintillators appeared. To satisfy the requirements of fast timing applications high photo-detection efficiency, e. i. a good spectral match between the scintillator and photodetector must be achieved. Cesium-based ternary chlorides could provide a red-shift (∼1.5 eV) of CL towards the sensitive region of the photodetector (PMT or SiPM) while keeping light output and timing characteristics comparable to BaF2.