Continuous-wave intracavity YVO4/BaWO4 Raman laser pumped by a wavelength-locked 878.9 nm laser diode

Abstract

In this paper, the composite Nd:YVO4 laser crystal is in-band pumped by a wavelength-locked laser diode at 878.9 nm, with the purpose of reducing thermal effects and improving pump absorption simultaneously. By using the YVO4 and BaWO4 crystals as Raman media, the influences of crystal properties, resonator structure and stability on the performance of continuous-wave intracavity Raman laser are investigated experimentally and theoretically. The results show that the resonator stability greatly affects laser performance due to the long cavity length of intracavity Raman laser. By choosing the Raman medium with high Raman gain, we can not only obtain higher Raman conversion efficiency, but also reduce the thermal effect to a certain extent. Furthermore, the smaller the curvature radius of the output mirror in the plano-concave cavity structure, the greater the power density of the fundamental laser in the Raman crystal is and the wider the dynamic stability region of the resonator, and hence the higher output power of the Raman laser can be achieved. Finally, by using 30-mm BaWO4 crystal as Raman medium, a highest Raman output of 3.02 W is obtained at a pump power of 25.1 W, corresponding to a diode-to-Stokes optical conversion efficiency of 12%.