Intense emission at 2.9 μm from Yb3+/Ho3+ co-doped TeO2-Ga2O3-ZnO tellurite glasses

Mid-infrared lasers have important applications in infrared countermeasures, sensing, environmental monitoring, biomedicine, and many military and civilian fields. In this work, an intense emission at 2.9 mu m from Yb3+/Ho3+ co-doped TeO2-Ga2O3-ZnO (TGZ) glass was reported. The 2 mu m, 1.2 mu m and visible emissions were also performed to understand the competitive luminescent mechanism. With the increase in Yb3+ concentration, all the emissions of Ho3+ increased, whereas the emission of Yb3+ decreased due to the phonon-assisted energy transfer from Yb3+ to Ho3+. The lifetimes of optimized 3 mol% Yb2O3 and 1 mol% Ho2O3 co-doped TGZ glass, which has the maximum emission intensity, are 548 mu s and 1.7 ms at 2.9 and 2 mu m, respectively. The Judd-Ofelt intensity parameters, absorption, and emission cross sections were calculated to evaluate the mid-infrared fluorescence properties of this new glass matrix material. The gain coefficients show that the 2 and 2.9 mu m laser gain can be realized by small pump energy, indicating that this glass is a promising medium for the mid-infrared optical fiber laser.

Automated summary

The Yb3+/Ho3+ co-doped TGZ glass exhibits strong emission at 2.9 microns, with Ho3+ emissions increasing and Yb3+ emissions decreasing as Yb3+ concentration increases due to energy transfer. The optimized glass with 3 mol% Yb2O3 and 1 mol% Ho2O3 shows potential for mid-infrared fiber laser applications.