Broadly tunable high-power Yb:Lu2O3 thin disk laser with 80% slope efficiency

We report on efficient laser operation of high quality crystalline Yb3+: Lu2O3 in thin disk configuration. Using doping concentrations between 1 at.% to 3 at.% and disk thicknesses between 0.08 mm and 0.45 mm the optimum crystal parameters have been determined. Pumped at 976 nm the laser operates at 1034 nm and 1080 nm. With a 0.25 mm thick 3 at.% Yb:Lu2O3 disk 32.6W of output power at 45.3W incident pump power with a slope efficiency of 80% and a resulting optical-to-optical efficiency of 72% have been realized. These are the highest values in terms of slope efficiency as well as optical-to-optical efficiency for an Yb-doped thin disk laser reported so far. Using an 1 mm birefringent filter continuous tuning from 987 nm to 1127 nm with more than 10 W of output power over a tuning range of 90 nm has been achieved. (C) 2007 Optical Society of America.