Tailoring the 1.5 μm emission performance of Er3+ in oxide and oxyfluoride tellurite glasses co-doped with Ce3+

This research investigates Er³⁺/Ce³⁺ co-doped oxide and oxyfluoride tellurite glasses synthesized under controlled dry atmosphere to evaluate how Ce³⁺ codoping and replacing ZnO with 0 to 15 mol% of ZnF₂ impact optical gain at 1.5 μm. Fourier-transform infrared (FTIR) analysis shows that adding ZnF₂ reduces the hydroxyl group absorption coefficient across all samples, suggesting reduced non-radiative relaxation. Furthermore, absorption spectroscopy revealed a shift of the absorption band towards longer wavelengths in the co-doped matrix compared to the one containing only Er³⁺, and the 1.5 μm lifetime analysis showed a systematic increase with ZnF₂ concentration. Therefore, the substitution of ZnO with ZnF₂ leads to a reduction in hydroxyl content and a potential increase in the excited-state lifetime of Er³⁺ NIR emission, suggesting that the synthesized glasses exhibit promising characteristics for future applications in optical amplifiers.