Influence of Yb3+ and Ce3+ codoping on fluorescence characteristics of Er3+-doped fluoride glass under 980 nm excitation

Fluorescence characteristics of Yb ³⁺:Ce ³⁺:Er ³⁺ -codoped fluoride glasses is reported. Yb ³⁺ codoping improved the excitation efficiency at 980 nm pumping and Ce ³⁺ codoping improved the branching ratio of the Er ^{3+ 4}I _11/2– ⁴I _13/2 transition level, resulting in an enhancement in the fluorescence quantum yield at 1550 nm. The energy transfer dynamics of the Yb ³⁺:Ce ³⁺:Er ³⁺ -codoped fluoride glass was also analyzed based on a rate equation model. The separately measured energy transfer rates between Yb ³⁺ and Er ³⁺, and between Er ³⁺ and Ce ³⁺ agreed to some extent with the theoretical simulation based on the rate equation model at a lower Yb ³⁺ concentration (<0.5 mol%).