Controlling nonadiabatic spectral redshift of high-order harmonic using two orthogonally polarized laser fields  

作　　者：Hongmei Wu Shengjun Yue Jinbin Li Silin Fu Bitao Hu Hongchuan Du 吴红梅;岳生俊;李金斌;伏思霖;胡碧涛;杜洪川(School of Nuclear Science and Technology, Lanzhou University;Key Laboratory of Special Function Materials and Structure Design, Ministry of Education,Lanzhou University)

机构地区：[1]School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000, China [2]Key Laboratory of Special Function Materials and Structure Design, Ministry of Education, Lanzhou University, Lanzhou 730000, China

出　　处：《Chinese Optics Letters》2018年第4期11-15,共5页中国光学快报（英文版）

基　　金：supported by the National Natural Science Foundation of China(NSFC)(Nos.11404153,11135002,11604119,and 11405077);the Fundamental Research Funds for the Central Universities of China(No.lzujbky-2017-14)

摘　　要：We investigate the nonadiabatic spectral redshift of high-order harmonic of He driven by two time-delayed orthogonally polarized laser fields. It is found that the nonadiabatic spectral redshift can be observed by properly adjusting the time delay of the two laser fields when the controlling pulse is added in the raising part of the driving pulse in the vertical direction. That is because the controlling pulse in the vertical direction prevents the ionized electrons from returning to the vicinity of parent ions and then reduces the recombination probability. This leads to the high-order harmonic generated mainly in the falling part of the driving pulse. Meanwhile,we also find that the quantity of redshift can be effectively controlled through accommodating the positive time delays. In addition, this scheme can also be used to produce nonadiabatic spectral blueshift.We investigate the nonadiabatic spectral redshift of high-order harmonic of He driven by two time-delayed orthogonally polarized laser fields. It is found that the nonadiabatic spectral redshift can be observed by properly adjusting the time delay of the two laser fields when the controlling pulse is added in the raising part of the driving pulse in the vertical direction. That is because the controlling pulse in the vertical direction prevents the ionized electrons from returning to the vicinity of parent ions and then reduces the recombination probability. This leads to the high-order harmonic generated mainly in the falling part of the driving pulse. Meanwhile,we also find that the quantity of redshift can be effectively controlled through accommodating the positive time delays. In addition, this scheme can also be used to produce nonadiabatic spectral blueshift.

关 键 词：Controlling nonadiabatic spectral redshift of high-order harmonic using two orthogonally polarized laser fields 

分 类 号：O56[理学—原子与分子物理]