Judd-Ofelt analysis of Eu3+ and Er3+ doped in ceramic BaGd2ZnO5

Judd-Ofelt (JO) analyses are performed on the efficient upconversion oxide phosphor Er3+:BaGd2ZnO5 as well as on the tunable phosphor Eu3+:BaGd2ZnO5. The refractive index of BaGd2ZnO5 found using the luminescence spectrum of Eu3+ is n = 2.17. The JO parameters for Eu:BaGd2ZnO5 are Ω2 = 9.71 × 10-20 cm2 and Ω4 = 6.15 × 10-20 cm2. The JO parameters of Er3+:BaGd2ZnO5 are Ω2 = 2.77 × 10-20 cm2, Ω4 = 1.61 × 10-20 cm2, and Ω6 = 0.60 × 10-20 cm2. The energy gap (ΔE = 879 cm−1) between 2H11/2 and 4S3/2 energy levels of Er3+ was obtained from a Fluorescence Intensity Ratio experiment. For the Er3+:BaGd2ZnO5, the calculations yielded the transition probabilities, branching ratios, radiative lifetimes, and quantum efficiency of the excited energy levels of Er3+ involved in upconversion.