Substitutional solubility limit for Ce3+ ions in Lu3Al5O12:xCe3+ and its effect on photoluminescence

The substitutional solubility for the Ce3+ ions in Lu3Al5O12 was estimated using crystal structure refinement and measurement of the luminescence. The photoluminescence excitation spectra of Lu3Al5O12:Ce3+ powders were composed of two peaks at approximately 347 nm and 450 nm, respectively, owing to the ground-state doublet of the Ce3+ ions, while a single emission band was observed in the green region. The solubility limit for the Ce3+ ions was determined by measurement of the actual Ce3+ concentrations in the particles, the refined crystal parameters, the evolution of the photoluminescence spectra, and the critical distance for energy transfer between the Ce3+ ions; the limits were approximately 1.7 and 3 mol% for 1600 and 1700 °C, respectively.