Study of the optical absorption and photoluminescence in (Pb,Gd)3(Al,Ga)5O12 : Ce epitaxial films grown from Pb-containing melt solutions

The optical absorption and photoluminescence properties of cerium-activated (Pb,Gd)₃(Al,Ga)₅O₁₂ epitaxial films are studied. The films are grown on single-crystal (111)-oriented Gd₃Ga₅O₁₂ substrates by liquid-phase epitaxy from supercooled PbO – B₂O₃ melt solutions at different concentrations of gadolinium, cerium, and aluminium oxides in the charge. The photoluminescence band of Ce³⁺ ions is shown to peak at 532 nm. The highest cathodoluminescence yield of about 51500 photons MeV^-1 at a decay time of the slow component of 61.0 ns (light yield fraction 68%) is found for the Pb_0.01Ce_0.03Gd_2.96Al_3.14Ga_1.86O₁₂ film, grown from melt solution with gadolinium oxide, cerium oxide, and aluminium oxide concentrations of 0.4, 0.2, and 4.5 mol % in the charge, respectively. Epitaxial films with these spectroscopic characteristics are promising for application in scintillation screens.