Study Of Ultraviolet Laser On A则-Solid-State Nd:GdVO₄-KBe₂BO₃F₂

The investigation around the Beijing Education Committee Foundation Program on the optical characteristics of Nd:GdVO₄ crystal and nonlinear optical crystal KBe₂BO₃F₂(KBBF) to research the deep ultraviolet laser of all solide state laser. The exploitation of the all solide ultraviolet laser is of great value, as it has many advantages such as high efficiency, small volume, high stability, etc. However, the deep ultraviolet wave is mainly depended on the frequency conversion at the present. So the laser crystals and the nonlinear optical crystals are important materials to obtain the deep ultraviolet lasers, determine its output properties. Nd:GdVO₄ crystal has many superiorities among the laser crystals, and the KBBF crystal has the shortest transparent wave band in deep ultraviolet for nonlinear crystals. So the crystal of Nd:GdVO₄ and KBBF can bring a bright futher to all solide state deep ultraviolet laser. We have carried out thoroughly theoretical investigation on the properties of Nd:GdVO4 and KBBF that can give some advices for the experiments of high power all solid ultraviolet laser using Laser Diode(LD) pumped Nd:GdVO4-KBBF. In the section one, we have studied on the properties of laser crystal Nd:GdVO4 according to the rate equation, and given numerical simulation and analysis of many factors such as pumping and oscillating beams, laser crystal length, intracavity loss, output morrirs transmission, input power, etc. That is influencing to the all solid laser of LD end-pumped Nd:GdVO₄ on its output power, threshold power and conversion efficiency. We obtained the pumping threshold power, output power of the threshold pumping power, and the optimal transmission of Nd:GdVO4 when the output power is 25W, and compared with Nd:YVO4 and Nd:YAG crystals. We calculated the Second Harmonic Generation(SHG), Third Harmonic Generation(THG), and angle tunable properties of KBBF crystal for the nonlinear optical crystal.We obtained SHG and THG factors of KBBF such as phase matching angle, effective nonlinear coefficient, walk-off angle, walk-off length, permitted angle and wavelength according to the momentum and energy conversion laws, and the Sellmeier equation of the KBBF in the type-I and type-II. Furthermore, we simulated the tunable curves of wavelengthes versus angle, and compared with the extensive used crystal BBO and CLBO.