High repetition frequency passively Q-switched Ho:YVO4 laser

Abstract We have demonstrated a high repetition frequency passively Q-switched Ho:YVO 4 laser with a Cr 2+ :ZnS saturable absorber pumped by a 1.94 μm Tm-fiber laser, for the first time to our knowledge, in this Letter. The maximum average output power of 8.1 W was achieved at the absorbed pump power of 30.4 W, corresponding to the minimum pulse width of 161.6 ns, pulse energy of 70.3 μJ and pulse repetition frequency of 114.6 kHz. In addition, the laser had beam quality factor of M x 2  ∼ 1.15 and M y 2  ∼ 1.09 at the output power of 5 W.