Passively mode-locked Yb:Lu(2)O(3) laser.

Given its specific thermal characteristics, the sesquioxide crystal Lu(2)O(3) is a particularly promising laser host material. We demonstrate mode locking of a Yb:Lu(2)O(3) laser by use of a semiconductor saturable-absorber mirror. The laser emits up to 470 mW in the picosecond regime, corresponding to a pump efficiency as high as 32%. With dispersion compensation, pulses as short as 220 fs at an average power of 266 mW are obtained at 1033.5 nm. To our knowledge, this is the first demonstration of a femtosecond oscillator based on Yb:Lu(2)O(3).