Application of original and modified Judd–Ofelt theories to the 1S0 state of Pr3+-doped SrAl12O19 and LaF3

The main fluorescence branching ratios of 1S0 state in SrAl12O19:Pr3+and LaF3:Pr3+ have been determined by vacuum ultraviolet excitation. The original and modified Judd–Ofelt analyses both with normalized method were applied to the absorption spectra of Pr3+ to get three phenomenological intensity parameters: Ω2, Ω4, and Ω6. They were subsequently employed to calculate the branching ratios and decay times of the Pr3+1S0 level in SrAl12O19 and LaF3. The result showed that in both hosts, the modified Judd–Ofelt theory with normalized method provided a better agreement with experimental data than the original one.