全反射相干自相关法测量飞秒脉冲的特性分析

 全反射相干自相关法在测量紫外-X光波段的超短脉冲和宽频带脉冲方面具有优势。借助数值模拟,比较了全反射相干自相关和传统相干自相关方法测量不同相位结构脉冲时信号特征的异同。利用自建的组合式自相关装置测量了钛宝石激光器输出的飞秒脉冲及经由40 mm厚BK7玻璃块展宽而成的啁啾脉冲。理论分析和实验结果表明,同一脉冲的两种自相关曲线是基本相似的,因而在传统自相关方法不适用或操作不便的情况下,可以用全反射相干自相关法来替代。

Characteristic Analysis on the Measurement of Femtosecond Pulses by All-Reflective Interferometric Autocorrelation

All-reflective interferometric autocorrelation is advantageous for the measurement of ultrashort pulses within UV to X-ray region or wideband pulses. By means of numerical simulation, comparison of the signal characteristics between the conventional and the all-reflective interferometric autocorrelations is made for ultrashort pulses with varied spectral phases. Femtosecond pulses from a Ti:sapphire laser as well as the chirped pulses stretched by a 40-mm-thick BK7 glass are measured by a home-made combined interferometric autocorrelator. The results show that the traces of two interferometric autocorrelations are quite similar for the same test pulses. Therefore, in situations that conventional autocorrelation is incapable or inconvenient for pulse measurement, all-reflective interferometric autocorrelation is competent to carry out the duties.