Stable high-power green light generation with a periodically poled stoichiometric lithium tantalate

Periodically poled stoichiometric lithium tantalate was used for an efficient high-power coherent green light generation based on second-harmonic generation (SHG) using a Q-switched Nd:YVO4 laser. Achieved conversion efficiency was 69% that corresponds to SHG power density of 21.6 MW/cm2 at the maximum input fundamental peak power density of 31.5 MW/cm2. The SHG power fluctuation was less than 3.4% for 35 h, which was mainly caused by input power fluctuation of 2.6%. Obtained SHG powers of 4.4 and 3.4 W were sufficiently stable without spatial beam distortion at room temperature and a phase matching temperature adjustment was required precisely at high input power.