Efficient passively Q switched lasers with a large-energy stored Yb:LuScO3 crystal.

ABSTRACT

Ytterbium (Yb)-ions-doped sesquioxide crystal is an attractive gain medium for a tunable and pulsed laser owing to its high thermal conductivity. In particular, it has been identified that YbLuScO3 has the largest energy storage property compared with other sesquioxide crystals, which is favorable for passive Q switching. In this Letter, continuous wave (CW) and the first, to the best of our knowledge, passively Q switched laser operations were demonstrated with a YbLuScO3 crystal. For CW laser operation, it generated the maximum output power of 8.68 W, corresponding to a slope efficiency up to 78.3%. Using CrYAG crystals as saturable absorbers, stable passive Q switching lasers were obtained with the YbLuScO3 crystal. Both the CW and Q switched lasers operate on the strongest fluorescence emission peak of 1038 nm. With CrYAG as the saturable absorber, efficient passively Q switched lasers with a slope efficiency of 45% were obtained with the pulse width, pulse energy, and peak power of 5.9 ns, 116 µJ, and 18.5 kW, respectively.