可调谐中红外强激光脉冲驱动下水窗波段阿秒脉冲的产生与表征

项目名称： 可调谐中红外强激光脉冲驱动下水窗波段阿秒脉冲的产生与表征

项目编号： No.11274325

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 郑颖辉

作者单位： 中国科学院上海光学精密机械研究所

项目金额： 90万元

中文摘要： 近年，人类已起步由飞秒时代向阿秒时代迈进。然而科学家们总是不断在时间、空间、频率等基本物理量上挑战极限。因此在追求尽可能短的持续时间的同时如何获得尽可能短的波长（尽可能高的频率）乃至水窗波段的阿秒相干光源是目前极为重要的研究热点与方向。高次谐波的截止频率与驱动激光波长的平方成正比，因此随着更长波段的可调谐中红外新波段强场超快激光的出现与迅猛发展，产生水窗波段乃至keV量级的高次谐波辐射并不困难，但是能更好地用于探测水中生物样品的电子动力学过程的还是单个阿秒脉冲。目前产生水窗波段的单个阿秒脉冲还是该领域亟待突破的前沿科学问题。本项目旨在利用目前新兴的可调谐中红外新波段强场激光驱动，探索利用多周期双色场技术，宏观位相匹配技术和分子的电荷共振增强电离效应等产生水窗波段单个阿秒脉冲，并探索研究水窗波段阿秒光脉冲的测量新方法对其进行表征。

中文关键词： 高次谐波；阿秒脉冲；水窗；；

英文摘要： Recently, human has strided from femtosecond era forward to attosecond era. However, sientists always challenge the limits of the basic physical quantities, such as time, space and frequency. Thus, pursuing the shortest possible duration, meanwhile how to generation the attosecond coherent laser source with the wavelength as short as possible (the frequency as high as possible), even in the water window, is a extremely vital research hotspot and intrest.The cut-off frequency of high-order harmonic is proportional to square of the wavelength of the driving laser field. So with the appearance and fast development of the tunable midinfrared intense ultrafast laser pulses with longer wavelength, it becomes not difficult to achieve high-order harmonic emission in the water window even in the keV region. Nevertheless, single attosecond pulses are more suitable for studying the ultrafast electronic dynamics of biological samples in water. So far, the generation of single attosecond pulses in the water window is a frontier scientific problem desiderated to break through. This project proposes the research on the generation and characterization of single attosecond pulses in the water window driven by the emerging tunable midinfrared intense laser field, using the multicycle two-color method, macroscopic phase-matched te

英文关键词： high-order harmonic；attosecond pulse；water-window；；