Upconversion fluorescences of TeO2- and Ga2O3-based oxide glasses containing Er3+

Abstract Upconversion-pumped fluorescence was observed for the first time in Er2O3-doped oxide glasses even at room temperature without any sensitizing ions such as Yb3+ in the systems of TeO2- and Ga2O3-based oxide glasses. A diode laser operating at 798 nm was used as the pumping source for stepwise excitation. The upconversion-pumped fluorescence was confirmed by the quadratic changes of fluorescence intensity against the pumping power. It is suggested that these oxide glasses can become one candidate for a high temperature upconversion device.