Emission efficiency at 1 µm from low Yb3+ concentrated tellurite glass-ceramics: Alternative materials for the future rare-earth metal shortage

Glasses in the TeO 2 -ZnO-Bi 2 O 3 system were prepared with up to 2.5 mol% of Yb 2 O 3 using standard melting process and their crystallization process was investigated for the first time. No concentration quenching was observed. The thermal treatment leads to surface precipitation of crystals, the composition of which depends on the Yb 2 O 3 content. The addition of Yb 2 O 3 in the tellurite network promotes the precipitation of Bi 2 Te 4 O 11 crystals at the expense of Zn 2 Te 3 O 8 crystals. The growing of these crystals in the low Yb 3+ concentrated glass during a thermal treatment increases the interaction between the Yb 3+ ions leading to an enhancement of the Yb 3+ emission properties which reach those of highly Yb 3+ concentrated tellurite glass. Our study suggests that a thermal treatment can be a practical alternative to increase the emission efficiency of the glass prepared with 0.5 mol% of Yb 2 O 3 to the level of the as-prepared glass doped with 2.5 mol% of Yb 2 O 3 .