充气毛细管中飞秒激光四波混频的理论描述

Theoretical description of four-wave mixing of femtosecond pulses in gas-filled capillary

建立了一个描写充气毛细管中飞秒激光四波混频过程的理论框架 .在这个理论框架的基础上 ,对最近得到的充气毛细管中飞秒激光四波混频过程的信号强度 气压实验曲线给出了初步的理论说明 .发现考虑走离效应和相调制效应对充气毛细管中飞秒激光四波混频过程有重要的作用 .同时还发现在一定的条件下 。

The coupled equations of four-wave mixing by femtosecond pulses in gas-filled capillary are derived. Based on the equations,the influence of the walk-off and phase modulation is investigated. It is found that the discrepancy between the theoretical and experimental results decreases when the influence of the walk-off and phase modulation is taken into account. At the same time,it is also found that taking the influence of the 3rd harmonic generated by the idler light into account is necessary for reducing the discrepancy between the theoretical and experimental results.