Research on Optically Pumped Vertical-External-Cavity-Surface-Emitting-Semiconductor Laser at 1178

A compact optically pumped vertical-external-cavity surface-emitting-semiconductor laser (OP-VECSEL) at 1178 nm for mu s pulsed operation is reported for the first time. The laser employed a V-shaped resonator with the cavity length of 300 mm, pumped by a 200 mu s pulse 808 nm laser operating at a repetition rate of 1 kHz. The maximum output power about 0.78W was obtained at pump power of similar to 5.9 W. The corresponding conversion efficiency from absorbed pump power to 1178 nm was 13.2%. Further, by the intra-cavity frequency doubling of the VECSEL, a mu s pulsed 589 nm laser has broad prospects in the application of sodium guide stars.