Spectroscopic investigation of Tm3+ doped tungsten-tellurite glasses sensitized by Yb3+
The Yb<sup>3+</sup>/Tm<sup>3+</sup> co-doped 60TeO<inf>2</inf>-30WO<inf>3</inf>-10La<inf>2</inf>O<inf>3</inf> glass with good thermal stability and efficient 1.8µm emission is reported. The energy transfer mechanism for both upconversion luminescence and the 1.8µm emission is discussed.