Spectral properties of Er3+/Yb3+ codoped tungsten–tellurite glasses

The spectral properties of Er3+/Yb3+ codoped tungsten–tellurite (WT) glasses have been investigated. The measured absorption spectra are analyzed by Judd–Ofelt theory. The compositional change of intensity parameter Ω2 is attributed to the change in the covalency between the Er3+ and oxygen ions, the asymmetry in the local structures around the Er3+ ions can be neglected. The lifetimes of 4I13/2 level of Er3+ in WT glasses are measured and comparable with other TeO2-based glasses. The stimulated emission cross-section is calculated based on McCumber theory. The florescence full width at half maximum (FWHM) and the emission cross-section (σpeak) of the 4I13/2 → 4I15/2 transition of Er3+ in different glass hosts have been compared. The suitability of such WT glasses as host materials for 1.5 μm broadband amplification is discussed.