O'Keeffe Kevin, Lloyd David T, Hooker Simon M
Opt Express. 2014 Apr 7;22(7):7722-32. doi: 10.1364/OE.22.007722.
A simple technique for generating trains of ultrafast pulses is demonstrated in which the linear separation between pulses can be varied continuously over a wide range. These pulse trains are used to achieve tunable quasi-phase-matching of high harmonic generation over a range of harmonic orders up to the harmonic cut-off, resulting in enhancements of the harmonic intensity in excess of an order of magnitude. The peak enhancement of the harmonics is clearly shown to depend on the separation between pulses, as well as the number of pulses in the train, representing an easily tunable source of quasi-phase-matched high harmonic generation.
展示了一种用于产生超快脉冲序列的简单技术，其中脉冲之间的线性间隔可以在很宽的范围内连续变化。这些脉冲序列用于在高达谐波截止的一系列谐波阶次上实现高次谐波产生的可调谐准相位匹配，从而使谐波强度增强超过一个数量级。谐波的峰值增强明显取决于脉冲之间的间隔以及脉冲序列中的脉冲数量，这代表了一种易于调谐的准相位匹配高次谐波产生源。
