SUM FREQUENCY OUTPUT OF 271-281.5nm IN BBO CRYSTAL
Lu Shiping Yang Lishu (Anhui Institute of Optics and Fine Mechanics, Academic Sinica, Hefei 230031)
The Rh·6G dye laser was pumped by a home-made Q-YAG laser. The tunable dye laser beam (562-598nm) was used to generate the sum frequency with the double-frequency beam of YAG laser in β-BaB2O4 (BBO) crystal. The continuously tunable range of 271-281.5nm was obtained. The output energies of sum frequency are larger than 200μJ. The largest conversion efficiency is about 5%. The tuning curves of sum frequency were calculated by BBO Sallmeier equations of C. Chen and K.Kato. The angular differential of phase matching angle of both theoretical tuning curves is about one degree. There are deflections in varying degree between the experimental curve and the theoretical calculated curves. But, the theoretical curve calculated by BBO Sellmeier equention of Kato is very close to the experimental curve. We have discussed the influence of BBO crystal length on the output energy, and explained the cause generating the influence.