宽带飞秒脉冲双折射干涉滤波的研究

Study on Birefringent Filter for Broad-Bandwidth Femtosecond Pulse

对宽带飞秒脉冲双折射干涉滤波进行了理论和实验研究。首先给出了一种新型的双折射干涉滤波器的原理和设计 ,得到了输出滤波光谱强度分布的解析表达式。然后进行了 15fs宽带脉冲的干涉滤波的实验研究 ,实验得到了一组性能良好的透射和反射输出的干涉滤波谱图 ,实验测量与理论计算基本一致。同时还分析了群速失配以及色散对宽带飞秒脉冲双折射干涉滤波的影响。结果表明这种滤波器对宽带飞秒脉冲有很好的干涉滤波作用 ,能同时前向透射和侧向反射干涉滤波输出 ,且无插入功率损耗 ,可以用来获得波长稳定的多波长可调谐超短脉冲光源。对于飞秒脉冲干涉滤波器的设计和应用具有重要的参考价值。

The birefringent interference filter for broad-bandwidth femtosecond pulse is investigated theoretically and experimentally. The principle and design of a novel birefringent filter are presented based on the interference of polarized light, the analytical formulation of transmission and reflection spectra out of the filter is obtained. The experiments of the filter for 15 fs broad-bandwidth pulse have been carried out, a group of good transmittance and reflection filter spectra is obtained in the experiments, the experimental measurements are in agreement with the theory. Moreover, the influence of the group velocity mismatch (GVM) and group velocity dispersion (GVD) on the filter for broad-bandwidth femtosecond pulse is analyzed. The results demonstrate that the filter is feasible and efficient for broad-bandwidth femtosecond pulse, and there is no power depletion since it allow output of the forward transmission and lateral reflection spectra synchronously. This kind of filter can be applied to developing stable multi-wavelength and tunable ultrashort pulse sources. The results can be importantly referenced by design and application of this kind of filter for femtosecond pulse.