Fabrication of a saturable absorber WS² and its mode locking in solid-state laser

We report on a passively mode-locked Nd: LuVO⁴ laser using a type saturable absorber of tungsten disulfide (WS²) fabricated by chemical vapor deposition method. At the pump power of 3.3 W, 1.18-W average output power of continuous-wave mode-locked laser with optical conversion efficiency of 36% was achieved. To the best of our knowledge, this is the highest output power of passively mode-locked solid-state laser based on WS². The repetition rate of passively mode-locked pulse was 80 MHz with the pulse energy of 14.8 nJ. Our experimental results show that WS² is an excellent type of saturable absorber.