Chen M-C, Gerrity M R, Backus S, Popmintchev T, Zhou X, Arpin P, Zhang X, Kapteyn H C, Murnane M M
Department of Physics and JILA, University of Colorado and National Institute of Standards and Technology, Boulder, Colorado 80309-0440, USA.
Opt Express. 2009 Sep 28;17(20):17376-83. doi: 10.1364/OE.17.017376.
By focusing a high repetition rate (50 kHz), compact, femtosecond laser system with low pulse energy (25 muJ) using a tight-focusing geometry, we demonstrate fully phase matched high-order harmonic generation for the first time at very high repetition rates, resulting in EUV light with full spatial coherence. The result is a practical, single-box, coherent source useful for applications in metrology, ultrafast spectroscopy, imaging and microscopy. The soft x-ray flux can be improved further by increasing the laser pulse energy and/or repetition rate.
通过使用紧密聚焦几何结构，聚焦一个具有高重复率（50千赫兹）、紧凑且脉冲能量低（25微焦）的飞秒激光系统，我们首次在非常高的重复率下演示了完全相位匹配的高次谐波产生，从而产生具有完全空间相干性的极紫外光。结果是得到了一个实用的、单盒式的相干光源，可用于计量学、超快光谱学、成像和显微镜等应用。通过增加激光脉冲能量和/或重复率，软X射线通量可以进一步提高。
