Generation of quasi-chirp-free isolated attosecond pulses from atoms under the action of orthogonal two-color combined pulse of fundamental frequency and higher intensity second harmonic fields

作     者：蔚瑞贤 乔月 李萍 王俊 陈基根 冯伟 郭福明 杨玉军 Rui-Xian Yu;Yue Qiao;Ping Li;Jun Wang;Ji-Gen Chen;Wei Feng;Fu-Ming Guo;Yu-Jun Yang

作者机构：Institute of Atomic and Molecular PhysicsJilin UniversityChangchun 130012China Jilin Provincial Key Laboratory of Applied Atomic and Molecular Spectroscopy(Jilin University)Changchun 130012China Zhejiang Provincial Key Laboratory for Cutting ToolsTaizhou UniversityJiaojiang 31800China 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2023年第32卷第6期

页      面：218-225页

核心收录：

学科分类：07[理学] 070203[理学-原子与分子物理] 0702[理学-物理学] 

基　　金：Project supported by the National Key Research and Development Program of China(Grant No.2019YFA0307700) the National Natural Science Foundation of China(Grant Nos.12074145,11627807,and 11975012) the Research Foundation for Basic Research of Jilin Province,China(Grant No.20220101003JC) the Fundamental Research Funds for the Central Universities of China(Grant No.30916011207) the Outstanding Youth Project of Taizhou University(Grant No.2019JQ002) 

主　　题：high-order harmonic orthogonal two-color fields relative phase quasi-chirp-free isolated attosecond pulses 

摘      要：The intrinsic chirp of high-order harmonic generation is an important factor limiting the production of ultrashort attosecond *** on numerically solving the time-dependent Schrodinger equation,the generation process of highorder harmonic from the He atom under the action of orthogonal two-color combined pulse of fundamental frequency and higher intensity second harmonic fields is *** this paper,we propose to achieve quasi-chirp-free isolated attosecond pulses by superimposing a higher second-harmonic field on the orthogonal direction of the fundamental frequency *** is found that the high-energy part of its harmonic emission exhibits small chirp characteristics,which can be used to synthesize isolated attosecond *** the analysis of the wave packets evolution and the classical motion trajectories of the electron,it is demonstrated that the quasi-chirp-free harmonic can be attributed to the simultaneous return of electrons ionized at different times to the parent *** influence of the relative phase of the two pulses on the harmonics is further analyzed,and it is observed that this phenomenon is sensitive to the relative phase,but it can still generate isolated attosecond pulses within a certain phase.