论文部分内容阅读
受激拉曼散射(SRS,StimulatedRamanscattering)属三阶非线性光学效应,它利用非弹性散射使入射激光产生一定频移,从而获得新波长激光,是一种有效的激光变频方式。我们利用波长为532nm,频率为10Hz的皮秒脉冲激光作为抽运源,采用单次通过方法实现了BaWO4晶体的受激拉曼散射。抽运光束的初始直径为4mm,采用一个由双透镜组成的缩束系统将其减小至1mm,以提高入射到晶体上的功率密度。BaWO4晶体为c向切割,长度为30mm,抽运光偏振沿晶体a向。用滤色片滤除晶体出射光束中的剩余抽运光,再用一个会聚透镜将产生的受激拉曼激光收集起来,用于能量及光谱的测量。
Stimulated Raman scattering (SRS) is a third-order nonlinear optical effect. It uses inelastic scattering to produce a certain frequency shift of the incident laser, so as to obtain a new wavelength laser, which is an effective laser frequency conversion method. We use the picosecond pulsed laser with a wavelength of 532 nm and a frequency of 10 Hz as the pumping source, and use the one-pass method to achieve stimulated Raman scattering of the BaWO 4 crystal. The initial diameter of the pump beam was 4 mm, which was reduced to 1 mm using a two-lens defocusing system to increase the power density incident on the crystal. BaWO4 crystal is c-cut, a length of 30mm, pumped polarized light along the crystal a. The filter is used to filter out the remaining pump light in the exit beam of the crystal, and then a convergent lens is used to collect the generated stimulated Raman laser for energy and spectral measurement.