研究了高压缩度压缩态光场制备中高斯光束的空间模式匹配问题。研究结果表明, 对于较小的目标腰斑, 注入光的腰斑位置和大小的允许偏移范围较小, 且模式匹配效率受腰斑位置偏离度的影响大, 而对于大腰斑, 情况则相反。此外, 激光光斑的椭圆率和像散、非线性晶体的热效应均会导致模式匹配效率下降。非对称结构的腔型可以扩大与光学参量腔匹配的激光束腰斑位置所允许的偏移范围, 更易实现高的模式匹配效率。

The spatial mode-matching problem of Gaussian beams in the preparation of squeezed field with a high compressibility is studied. The study results show that, for a small target spot, the allowed deviation ranges of the waist position and size of the injected beam are small, and the mode-matching efficiency is more sensitive to the deviation of the waist position, while for a large target spot, the situation just reverses. In addition, the ellipticity and astigmatism of the laser spot and the thermal effect of the nonlinear crystal can lead to the decrease of the mode-matching efficiency. An asymmetric cavity can expand the allowed deviation range of the waist position which matches with optical parametric oscillators, which is easier to obtain a higher mode-matching efficiency.