Luminescence and Judd–Ofelt analysis of the Pr³⁺ doped fluorotellurite glass

Praseodymium doped TeO₂–BaF₂–NaF glasses were prepared by conventional quenching melt technique. Optical absorption spectra have been investigated using Judd–Ofelt (JO) theory. Radiative transition probabilities and branching ratios were calculated. The branching ratios for the ¹D₂→³F₄ and ³P₀→³F₂ emission transitions are above 40%. The fluorescence of Pr³⁺ in the visible bands was observed under 325 nm pumping. The energy transfer and concentration quenching have been discussed. The ¹D₂ emission quenches much faster than those of ³P₀ due to the cross-relaxation between ¹D₂→¹G₄ and ³H₄→³F₄ transitions, which provides an appropriate interpretation for the red shift of emission band around 600 nm. The decay curves of ³P₀ level are measured. In 0.5 mol% Pr³⁺ doped sample, we obtained maximum lifetime is 21.5 μs. The prepared glasses are potential candidates for laser applications. - Highlights: • Optical character of Pr³⁺ doped TBN glasses have been investigated using Judd–Ofelt (JO) theory. • The branching ratio for Pr³⁺:¹D₂→³F₄ and ³P₀→³F₂ emission transitions are above 40%. • The energy transition and concentration quenching have been discussed. • Cross-relaxation between Pr³⁺:¹D₂→¹G₄ and ³H₄→³F₄ caused fluorescence quenching. • A new phenomenon provides an interpretation for the red shift of emission band around 600 nm