靶源位置对强场高次谐波相位匹配的影响  

Effect of target position on phase matching in high-order harmonic generation

作　　者：王超[1] 康轶凡[2] 白永林[1] 王屹山[3] 徐鹏[1] 王向林[3] Wang Chao;Kang Yifan;Bai Yonglin;Wang Yishan;Xu Peng;Wang Xianglin(Key Laboratory of Ultra-fast Photoelectric Diagnostics Technology,Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences,Xi’an 710119,China;School of Science,Air Force Engineering University,Xi’an 710051,China;State Key Laboratory of Transient Optics and Photonics,Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences,Xi’an 710119,China)

机构地区：[1]中国科学院西安光学精密机械研究所,中科院超快诊断技术重点实验室,西安710119 [2]空军工程大学理学院,西安710051 [3]中国科学院西安光学精密机械研究所,瞬态光学与光子技术国家重点实验室,西安710119

出　　处：《强激光与粒子束》2018年第10期3-6,共4页High Power Laser and Particle Beams

基　　金：国家自然科学基金项目(11675258;61690222;11505289);中国科学院国家外国专家局创新团队国际合作伙伴计划项目

摘　　要：为提高强激光场与惰性气体靶作用产生的孤立阿秒激光脉冲的能量,给出了一种实现高次谐波过程中最佳谐波相位匹配的定量实验方法。研究了气体靶源与高斯型驱动激光场聚焦点相对空间位置对谐波相位匹配及谐波产率的影响,得出了其最佳相位匹配位置始终位于驱动激光场聚焦点后3!5 mm,而在聚焦点之前的位置区域,严重的高次谐波相位失配导致谐波产率非常低。同时,在最佳相位匹配条件下,高次谐波场与驱动场具有相类似的空间强度分布特性,该结果印证了目前通常采用的高次谐波场为高斯光束的假设。This paper presents an experimental method to realize the best high-order harmonic generation(HHG)phase matching in the interaction of strong optical field and gas target.By studying the effects of the relative location between gas target source and Gaussian-type driving field focus on the harmonic phase matching,conclusions are obtained that the optimum position of gas target for phase matching is always 3-5 mm behind the focal point of the driving field,with much lower HHG yield before the focus caused by serious harmonic phase mismatch.At the same time,in the optimum relative position,the driving field and the high-order harmonic field have similar spatial distribution characteristics,providing the experimental basis for the commonly used assumptions of Gaussian beam for high-order harmonic field.

关 键 词：极端非线性光学 高次谐波产生 相位匹配 孤立阿秒脉冲 气体靶 

分 类 号：O437[机械工程—光学工程]