Fluorescence Lifetime Increasing with F^- Ions into Ytterbium-Doped Germanium--Lead--Tellurite Glasses

The effects of F^- ions in a germanium--lead--tellurite glass system on the spectral and potential laser properties of the Yb³⁺ are investigated. The absorption spectra, lifetimes, the emission cross-sections and the minimum pump intensities of the glass system with and without F^- ions have been measured and calculated. The results show that the fluorescence lifetime and the minimum pump intensity of Yb³⁺ ions increase evidently, which indicates that germanium--lead--oxyfluoride tellurite glass is a promising laser host matrix for high power generation. FT-IR spectra were used to analyse the effect of F^- ions on OH^- groups in this glass system. Analysis demonstrates that addition of fluoride removes the OH^- groups and results in improvement of fluorescence lifetime of Yb³⁺.