Co2+:LMA crystal as saturable absorber for a diode-pumped passively Q-switched Nd:YVO4 laser at 1342 nm

We have demonstrated an efficient diode-pumped passively Q-switched Nd:YVO4 laser at 1342 nm by using an uncoated Co2+:LaMgAl11O19 (Co2+:LMA) crystal as the saturable absorber. With the absorbed pump power of 11.7 W, the pulse width could be as low as 42 ns, with a corresponding average output power of 580 mW. At around 40 kHz repetition rate, the energy of a single Q-switched pulse was estimated to be about 14.5 mu J and the peak power was 346 W. The passive Q switching operation for the Co2+:LMA in different polarization states was also investigated.