飞秒光参量放大技术原理及应用

飞秒光参量放大技术是一种获得宽带飞秒脉冲的有效手段.首先介绍了飞秒光参量放大技术的基本原理,并通过数值模拟显示了群速度失配及位相失配对信号转换过程的影响.数值计算结果表明:群速度失配及位相失配会导致转换效率下降,群速度失配还会导致脉冲发生畸变.其次,综述了该技术在超短脉冲特别是周期量级脉冲产生方面的研究进展,并介绍了Baltuska等设计的可以产生3.9 fs脉冲的非共线光参量放大装置.其中,详细讨论了超连续白光注入源、泵浦光角色散以及晶体选择三方面内容.最后介绍了该技术在高能飞秒脉冲产生方面取得的最新研究进展.

Principle and application of femtosecond optical parametric amplification

Femtosecond optical parametric amplification is an effective means of generating broadband ultrashort pulses.First,the theoretical background of this technology is pre- sented.Numerical simulations are carried out to show the impact of group-velocity mismatch and phase mismatch.The results suggest that phase mismatch can reduce the conversion efficiency,while group velocity can simultaneously bring down the conversion efficiency and introduce distortion to the signal pulse.Second,some progress and latest advances concerning ultrshort pulses,especially few-cycle pulses generation are reported.A specific noncollinear optical parametric amplification system used for generating 3.9 fs pulses is introduced.Super- continuum injection,angular dispersion of pump beam and choice of operating medium are analyzed in detail.Finally,the latest achievement in acquiring high-power femtosecond pulses through this technology is presented.