Spectroscopic properties of 2.7 μm emission in Er3+ doped telluride glasses and fibers

Telluride glasses with high Er3+ doping concentration and good thermal property are prepared. Energy transfer processes for 1.5 μm, and 2.7 μm, as well as visible emission are fully discussed. Enhanced 2.7 μm emission is achieved from the bulk glass. An Er3+ doped fiber is successfully drawn, and strong upconversion emission is observed in the fiber.