Characterization and comparison of 1% at Yb-doped Lu2O3 and Sc2O3 ceramics as laser gain media

We present the first laser oscillation achieved on Ybdoped Sc2O3 and Lu2O3 ceramics with a levelof doping as low as 1 at %, under quasicontinuous wave pumping at 968 nm. Ceramic samples reached comparable performances in terms of tunability ranges, which exceeds 41 nm, and laser output powers. In particular, with the former sample emitting at 1040.5 nm we measured a maximum output power of 2.2 W with acorresponding slope efficiency of ? = 59%. The latter medium delivered 1.8 W with a slope of ? = 45% at1032.5 nm while at 1078 nm we measured 1.5 W with ? = 34%. Finally, we report the measured level of theAmplified Spontaneous Emission (ASE) for both samples, which was found to be less than 0.1 mW at themaximum pump power.