Passively Q-switched diode-pumped continuous-wave Md : YAG-Cr4+: YAG laserwith high peak power and high pulse energy

A high peak power and high pulse energy passively Q-switched diode-pumped c w Nd:YAG laser at 1.064-mu m wavelength has been demonstrated with Cr4+:YAG crystal as the saturable absorber. The average output power of 7-12 W and pulse duration of 100-250 ns was obtained with kilohertz repetition rates. The highest peak power and pulse energy obtained were 30 kW and 3.4 mJ, res pectively. All the output resulted from the TEM00, mode with M-2 < 1.1. The thermal lensing effect of the saturable absorber was investigated, demonst rating that it played an important role in optimization of the output. (C) 2000 Optical Society of America OCIS codes: 140.3540, 140.3480, 140.6810, 1 40.5680.