Optical and Scintillation Characteristics of Tb-doped La2Si2O7 Single Crystal

Lanthanum pyrosilicate La 2 Si 2 O 7 (LaPS) single crystals were successfully fabricated by the floating zone (FZ) method with Tb doping concentrations of 0.1, 0.5, 1.0, and 2.0% for scintillation and photoluminescence (PL) study.X-ray diffraction patterns of the samples indicate a single phase of LaPS from their consistency with the reference pattern.Tb-doped LaPS has multiple emissions from Tb 3+ 4f-4f transitions including those at 380, 420, 440, 480, 540, 590, and 620 nm, as observed in both PL and X-ray-induced scintillation spectra with a PL quantum yield of up to 50.1%.The PL and scintillation decay time constants obtained were 2.64-3.26and 1.54-2.00ms, respectively.In 137 Cs (662 keV) γ-ray pulse area spectra, the 1.0% Tb-doped LaPS had the highest scintillation light yield of 47700 ph/MeV.From all the results in this study, the optimum Tb doping concentration in LaPS single crystals is considered to be 1.0% for scintillator application.