Efficient 2.7 μm emission and energy transfer mechanism in Er3+ doped Y2O3 and Nb2O5 modified germanate glasses

•Er3+ doped Y2O3 and Nb2O5 modified germanate glasses were prepared.•The investigated samples possess superior thermal property.•Judd-Ofelt parameters and radiative properties are calculated and analyzed.•Large emission cross section and high radiative probability at 2.7 μm are achieved.•A reasonable energy transfer mechanism is proposed.

In this paper, Er3+ doped Y2O3 and Nb2O5 modified germanate glasses possessing good thermal stability are reported. On the basis of absorption spectra and Judd-Ofelt theory, a detailed investigation of Judd-Ofelt intensity parameters (Ω2,4,6) and radiative properties is carried out. Moreover, emission cross section at 2.7 μm is calculated based on Füchtbauer-Ladenburg equation and compared with other Er3+ doped glass systems. A reasonable energy transfer mechanism is proposed. It is interesting that the emission cross section and radiative transition probability in 5 mol% Nb2O5 modified germanate glass are much larger than those with 5 mol% Y2O3. Results indicate that present germanate glasses along with excellent 2.7 μm spectroscopic performance might have potential application for mid-infrared fiber laser.

Graphical abstractDownload high-res image (150KB)Download full-size image