Mid-infrared emission and Raman spectra analysis of Er^3+-doped oxyfluorotellurite glasses

This paper reports on the spectroscopic and structural properties in Er3+-doped oxyfluorotellurite glasses. The compositional variation accounts for the evolutions of Raman spectra, Judd–Ofelt parameters, radiative properties, and fluorescent emission. It is found that, when maximum phonon energy changes slightly, phonon density plays a crucial role in quenching the 2.7 μm emission generated by the Er3+∶I11/24→I413/2 transition. The comparative low phonon density contributes strong 2.7 μm emission intensity. The high branching ratio (18.63%) and large emission cross section (0.95×10−20 cm2) demonstrate that oxyfluorotellurite glass contained with 50 mol.% TeO2 has potential application in the mid-infrared region laser.