Fabrication and laser operation of Yb:Lu2O3 transparent ceramics from co-precipitated nano-powders

In this article, 5 at.% Yb:Lu2O3 transparent ceramics were fabricated by vacuum sintering combined with hot isostatic pressing (HIP) posttreatment using co-precipitated nano-powders. The influence of precipitant molar ratio, ammonium hydrogen carbonate, to metal ions (AHC/M3+, R value) on the properties of Yb:Lu2O3 precursors and calcined powders was investigated systematically. It was found that the powders with different R value calcined at 1100 degrees C for 4 hours were pure cubic Lu2O3 but the morphologies of precursors and powders behaved differently. The opaque samples pre-sintered at 1500 degrees C for 2 hours grew into transparent ceramics after HIP posttreatment at 1750 degrees C for 1 hour. The final ceramic with R = 4.8 showed the best optical quality with the in-line transmittance of 79.7% at 1100 nm. The quasi-CW laser operation was performed at 1034 nm and 1080 nm with a maximum output power up to 8.15 W as well as a corresponding slope efficiency of 58.4%.