High electro-to-optical efficiency 180 W Q-switched 532 nm laser with a pulsewidth of 70 ns

摘要

A compact straight cavity with two side-pumped Nd:YAG laser heads and a 90° quartz rotator in between is presented. By intracavity-frequency-doubling with a type II LBO crystal in this cavity, an output power of 180.2 W at 532 nm with a repetition rate of 10 kHz was achieved, corresponding to an electrical-to-optical efficiency of 10.9%. To best of our knowledge, this is the highest electrical-to-optical efficiency of the high power green lasers with above 100 W output power, ever reported. The pulsewidth was 70 ns and the peak power was 257.4 kW. The beam parameter product (beam waist multiplied by half beam divergence angle) was estimated to be 4.2 mmmrad and the power fluctuation over 2.5 hours was calculated to be better than ±1.2%.