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摘要运用多参考微扰理论(Multireference MΦller-Plesset theory)计算了SSCH3垂直激发能及其S-C与S-S两种断键方式的绝热(Adiabatic)与非绝热(Diabatic)的基态和激发态势能曲线, 研究了在193nm激光作用下SSCH3的光解离过程, 理论计算值与实验值相符. 相似文献
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The thermal effect and the heat generation in diode-end-pumped continuous-wave 914-nm Nd:YVO4 lasers are investigated in detail. A theoretical model of a diode end-pumped solid-state laser is constructed to analyse the influence of fractional thermal loading on the thermal effect in the Nd:YVO4 laser based on finite element analysis. The thermal focal lengths and the end-surface deformations of laser rods in Nd:YVO4 quasi-three-level and four-level lasers are measured and compared with the results obtained by ordinary interferometry for the demonstration of higher thermal loading in 914-nm laser. Finally the fractional thermal loading in the Nd:YVO4 quasi-three-level laser is calculated by matching the experimental and the simulated end deformations. 相似文献
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We present a high power and efficient operation of the ^4F3/2 → ^4I9/2 transition in Nd:GdVO4 at 912nm. In the cw mode, the maximum output power of 8.6 W is achieved when the incident pump power is 40.3 W, leading to a slope efficiency of 33.3% and an optical-optical efficiency of 21.3%. To the best of our knowledge, this is the highest cw laser power at 912nm obtained with the conventional Nd:GdVO4 crystal. Pulsed operation of 912nm laser has also been realized by inserting a small aeousto-optie (A-O) Q-Switch inside the resonator. As a result, the minimal pulse width of 20ns and the average laser power 1.43 W at the repetition rate of lOkHz are obtained, corresponding to 7.1 kW peak power. We believe that this is the highest laser peak power at 912nm. Furthermore, duration of 65ns has also been acquired when the repetition rate is 100 kHz. 相似文献