光学晶体K2Al2B2O7相位匹配参量放大研究

对K2Al2B2O7（KABO）晶体的相位匹配飞秒激光参量放大（OPA）特性进行了系统的理论计算和分析。分别讨论了Ⅰ型、Ⅱ型参量放大共线以及非共线情况，计算了在不同非共线夹角下的相位匹配角度。研究结果表明：对于一定波长的抽运光，存在一定的非共线入射角对应一定波长的信号光。在KABOⅠ型参变条件下，非共线角的引入使相位匹配角增大。这对于高效率地产生脉宽极短的飞秒参量激光、扩大飞秒激光的调谐范围以及通过参量技术放大飞秒脉冲都具有重要的意义。

Investigation on Phase Matched Optic Parametric Amplification Using K2Al2B2O7 Crystal

The phase-matched femtosecond OPA based on the K2Al2B2O7 （KABO）crystal is calculated and analyzed theoretically. The conditions to collinear and non-collinear in the Type-Ⅰ and Type- Ⅱ phase matching are investigated and the phase matching angle is calculated under different non-collinear angles. For the certain pump wavelength and signal wavelength, it is indicated that the non-collinear incident angle exists. Non-collinear phase matching is beneficial to parametric conversion efficiency＇ s increase in KABO crystal Type-Ⅰ phase matching femtosecond OPA. These properties are of great significance for efficiently producing and amplifying very short femtosecond parametric laser pulses with a wide tunable range.