Optical and structural properties of (70−x−y)TeO2-20WO3-10Y2O3-xEr2O3-yYb2O3 glasses

With regard to the optical analysis, an increase of the intensity of the upconversion emission with the increase of the content of the sensitizer ions Yb3+ was observed. The Er3+ emission around 1540 nm has a full width at half maximum of about 100 nm in the temperature range of 70-300 K, which is a very interesting value relatively to those reported for other glassy systems, considering optical amplification as a potential application.