Spectroscopy and laser operation of highly-doped 10 at.% Yb:(Lu,Sc)2O3 ceramics

International audienceHighly-doped “mixed” transparent sesquioxide ceramics, 10 at.% Yb:(Lu2/3Sc1/3)2O3, are fabricated by vacuum sintering at 1700 °C followed byhot isostatic pressing (HIPing) at 1680 °C and 200 MPa. The ceramics are of single-phase nature with a cubic (C-type, a = 10.191 Å) structure and a mean grain size of 0.66 µm. They feature high low-signal transmission of 79.0% at 1.20 µm. The Yb3+ ions in “mixed” ceramics exhibit strong inhomogeneous broadening of the absorption and emission bands, with σSE of 0.43×10-20 cm2 at 1079.4 nm and an emission bandwidth of 25.7 nm. The radiation-trapping-free luminescence lifetime is 163 µs. The crystal-field splitting for Yb3+ ions is revealed at 12 K. The Yb ceramic laser generated a maximum peak output power of 250 mW at ~1.04 and 1.08 µm with a slope efficiency of 40.3%. The ceramics are promising for mode-locked lasers at ~1.08 µm, including thin-disk geometry