H_2^+分子与共振相关的阈下谐波的取向效应  

Orientation Effects for Resonance-related Below-threshold Harmonics from H_2^+ Molecules

作　　者：田轶群[1] 董福龙[2] 李卫艳[2,3] 杨世平[2] 陈彦军[1] TIAN Yi-qun DONG Fu-long LI Wei-yan YANG Shi-ping CHEN Yan-jun(College of Physics and Information Technology, Shaan＇xi Normal University, Xi＇an 710119, China College of Physics and Information Engineering, Hebei Normal University, Shijiazhuang 050024, China School of Mathematics and Science, Hebei GEO University, Shijiazhuang 050031, China)

机构地区：[1]陕西师范大学物理学与信息技术学院,西安710119 [2]河北师范大学物理学与信息工程学院,石家庄050024 [3]河北地质大学数理学院,石家庄050031

出　　处：《光子学报》2017年第2期111-120,共10页Acta Photonica Sinica

基　　金：国家自然科学基金(No.11274090);中央高校基础研究基金(No.GK201403002);河北省自然科学基金(No.A2015205161)资助~~

摘　　要：通过数值模拟的方法研究了H_2^+阈下谐波的取向效应.数值模拟过程中,主要关注波长为760nm的阈下谐波,通过逐次减去激发态贡献的方法,研究共振相关谐波不同取向角下的变化规律.结果表明:阈下平行、垂直谐波展示的复杂取向依赖与共振效应密切相关,该现象主要由与基态共振的各激发态的轴对称性导致.另外,用包含跃迁偶极子的简单模型对取向效应进行了概括描述,并以H_2^+第一激发态为演化初始态进行了验证.本文结果可为阈下谐波取向效应的实验研究提供参考.The orientation effect for Below-Threshold Harmonics （BTHs） from H2 ＋ was studied through the numerical simulations. With excluding the contributions of excited states successively, the orientation dependence of BTHs, obtained with the driving laser wavelength of 760 nm, was analyzed in detail. The research results show that the complex orientation dependence of BTHs parallel and perpendicular to the laser polarization is closely related to the resonance effect between the ground state and the neighboring excited states, where the axis symmetry of these excited states play an important role. A simple model which contains the transition dipole is used to explain these complex orientation-related phenomena. The main results are checked with using the first excited state as the initial evolution state. The results can give suggestions on relevant experimental studies of orientation dependence of BTHs.

关 键 词：阈下谐波 取向效应 数值模拟 对称分子 共振效应 轴对称性 

分 类 号：O562[理学—原子与分子物理]