相位匹配法在毛细管波导中产生高次谐波的分析

Analysis of the Phase Matched High-Order Harmonics Generation in a Hollow Fiber Wave Guide

在理论上研究了超短强激光脉冲与毛细管中惰性气体相互作用产生高次谐波的最佳相位匹配条件 ,在计算中发现了特定级次谐波相位匹配中截止驱动光强的存在。分析表明要想使高次谐波获得相位匹配 ,需要超短脉宽的驱动脉冲以及电离能大的气体工作介质。讨论了毛细管波导中的强场高次谐波选择性并指出了改善谐波选择性的措施。

The phase matching of high order harmonic generated in rare gases confined in a hollow fiber wave guide is studied theoretically. A cutoff intensity for a certain phase matched harmonic is found in calculations. The calculations show that a ultrashort pulse laser and the medium with higher ionization potential is necessary for generating higher order phase matched harmonic. The possibility of selective generation of a certain order or several orders of harmonics in the hollow fiber wave guide is discussed, and some measures of improving the possibility of selectivity for a certain order or several orders of harmonics are advised.