强激光场驱动下CO_(2)分子的非序列双电离产量  

Yield of Non-Sequential Double Ionization of CO_(2) Molecules Driven by Intense Laser Fields

作　　者：刘可盈 白丽华[1] 郭祯 葛振杰 Liu Keying;Bai Lihua;Guo Zhen;Ge Zhenjie(Department of Physics,College of Sciences,Shanghai University,Shanghai 200444,China)

机构地区：[1]上海大学理学院物理系,上海200444

出　　处：《光学学报》2023年第20期1-9,共9页Acta Optica Sinica

基　　金：上海市自然科学基金(18ZR1413600)。

摘　　要：运用经典系综方法研究了线偏振激光场和双色反旋圆偏振激光场中CO_(2)分子非序列双电离的产量。结果表明:在激光强度较高的区域,双色反旋圆偏振激光场下CO_(2)分子非序列双电离的产量高于线偏振激光场;在激光强度较低的区域,结果则刚好相反。这是因为当激光强度较低时,CO_(2)非序列双电离产量的主要影响因素是抑制势垒,当激光强度较高时,由于抑制势垒发生扭曲,其产量主要受激光场结构的影响。Objective The interaction of atoms,molecules,and laser fields can generate many interesting nonlinear phenomena in the research on strong field physics.Among them,non-sequential double ionization(NSDI)has become a research hotspot.In the past,people mainly studied phenomena related to NSDI in the monochromatic laser field.With the continuous development of laser technology,a combined electric field has been applied to the study of NSDI for atoms and molecules.The electric field is composed of two circularly polarized(CP)laser fields with fixed frequency and is also called two-color CP laser field.At present,the counter-rotating two-color circularly polarized(CRTC)laser field is widely applied in research on enhancing the NSDI yield due to its special electric field structure.In recent years,studies have shown that the CRTC laser field is beneficial to increase the NSDI yield for O_(2).However,for triatomic molecules with more nuclei,whether the CRTC laser field can still increase the NSDI yield is an unexplored question.The dynamics of linear triatomic molecules(CO_(2))in the linearly polarized(LP)laser field and CP laser field have been studied,but there are few studies on the CO_(2) dynamics in CRTC laser fields.Therefore,we compare and analyze the NSDI yield for CO_(2) driven by intense laser fields,and further complement the research on the electron dynamics process in NSDI of linear triatomic molecules.Methods The method we adopt is based on the classical ensemble method for solving the time-dependent Newton equation.This method has been widely employed in the study of strong laser fields and atomic-molecular interactions.The NSDI electron dynamics of atomic molecules are simulated through the classical ensemble method in the following three steps.First,a stable initial ensemble is obtained.Second,the laser field components are added to the time-dependent Newton equation,and the initial ensemble is substituted to obtain the final coordinates and momentum distribution of the electrons.Third,the data with doub

关 键 词：原子与分子物理学 非序列双电离 双色反旋圆偏振激光场 线偏振激光场 分子 产量 

分 类 号：O562.4[理学—原子与分子物理]