Mid-infrared laser operation of (Er_0.07La_0.10Y_0.83)₂O₃ sesquioxide ceramic

Abstract A transparent sesquioxide ceramic (Er0.07La0.10Y0.83)2O3 was fabricated by vacuum sintering at 1780 °C for 3 h with lanthana acting as a sintering additive. It was of single-phase nature (sp. gr. Ia 3 ˉ ) with a close-packed microstructure (average grain size: 17 μm, pore content: 5 ppmv) and high transparency of 80% at 1.1 μm. The La3+ ions induced additional inhomogeneous broadening in the absorption and emission spectra of Er3+ ions. For the 4I11/2→4I13/2 transition, the stimulated-emission cross-section σ SE was 1.06 × 10−20 cm2 at 2719 nm and the luminescence lifetimes of the 4I11/2/4I13/2 states amounted to 2.73/5.91 ms, respectively. A (Er0.07La0.10Y0.83)2O3 ceramic laser generated 300 mW at 2840 nm with a slope efficiency of 27.7% and a laser threshold of only 17 mW.