A novel La3Ga5SiO14 electro-optic Q-switched Nd:LiYF (Nd:YLF) laser with a Cassegrain unstable cavity

A Nd:LiYF (Nd:YLF) laser which is actively electro-optic Q-switched with a La3Ga5SiO14 single crystal was designed. Each end of the Nd:YLF rod was cut at Brewster's angle, which ensures operation at 1.053 μm and saves the need of a polarizor. The dynamic to static rate, the insertion loss and the optical damage threshold of LGS Q-switch is 76%, 2% and 950 MW/cm2, respectively. Compared with KD2PO4, LGS is lack of water-solubility in air. When the pump energy is 121 J, the energy of single pulse output is 275 mJ with the repetition rate of 3 Hz and the beam divergence angle of 0.7 mrad. The mode of operation, the input-output characteristics and linear polarization ratio of this laser are also discussed.