Yamane K, Kito T, Morita R, Yamashita M
Opt Express. 2004 Jun 14;12(12):2762-73. doi: 10.1364/opex.12.002762.
Using 3.6- and 5.3-fs pulses, we demonstrated theoretically and experimentally that fringe-resolved autocorrelation (FRAC) traces are distorted by bandwidth limitations of the second-harmonic generation (SHG) in 10-microm-thick, type I ss-BaB2O4 for pulses shorter than sub-5 fs. In addition, detailed numerical analysis of the SHG showed that the optimum crystal angle where the FRAC trace distortion becomes minimum is in disagreement not only with the phase-matching angle but also with the angle where the FRAC signal intensity becomes maximum. Furthermore, the apparent pulse duration measured at a nonoptimum angle was confirmed to become shorter than that of its transform-limited pulse, in excellent agreement with the calculated result.
使用3.6飞秒和5.3飞秒脉冲，我们通过理论和实验证明，对于短于5飞秒的脉冲，在10微米厚的I型偏硼酸钡（ss-BaB2O4）中，二次谐波产生（SHG）的带宽限制会使条纹分辨自相关（FRAC）迹线发生畸变。此外，对SHG的详细数值分析表明，FRAC迹线畸变最小的最佳晶体角度不仅与相位匹配角不一致，而且与FRAC信号强度最大的角度也不一致。此外，在非最佳角度测量的表观脉冲持续时间被证实比其变换极限脉冲的持续时间短，这与计算结果非常吻合。
