飞秒激光参数对四态阶跃型分子光电子能谱的影响

计算物理 ›› 2016, Vol. 33 ›› Issue (4): 453-459.

飞秒激光参数对四态阶跃型分子光电子能谱的影响

李月华, 郭玮

南华大学电气工程学院, 湖南衡阳 421001

收稿日期:2015-05-20 修回日期:2015-08-12 出版日期:2016-07-25 发布日期:2016-07-25
通讯作者: 郭玮,E-mail:vella99@163.com
作者简介:李月华(1974-),女,硕士,讲师,从事强激光与物质相互作用研究,E-mail:bhylyh.com@163.com
基金资助:
国家自然科学基金（11447020）和湖南省自然科学基金（2015JJ3104）资助项目

Photoelectron Spectra of Four-Level Ladder Molecules: Effect of Femtosecond Laser Parameters

LI Yuehua, GUO Wei

School of Electrical Engineering, University of South China, Hengyang 421001, China

Received:2015-05-20 Revised:2015-08-12 Online:2016-07-25 Published:2016-07-25

摘要/Abstract

摘要： 利用含时波包法研究三激光场中四态阶跃型K₂分子光电子能谱的Autler-Townes（AT）分裂.研究第二束激光场强和波长对AT分裂的影响.共振时，光电子谱为对称三分裂，非共振时，不对称三分裂逐渐变为双分裂.波长增加，谱峰以不等位移向低能方向移动.边峰间距不随波长的改变而改变，随场强增强而增大.研究结果为进一步从第一性原理的理论研究提供有用的信息，为实现分子的光控制及量子调控提供重要参考.

关键词: 含时波包法, 四态阶跃型K₂分子, 光电子能谱, Autler-Townes分裂

Abstract: Autler-Townes (AT) splitting in photoelectron spectra of four-level ladder K₂ molecule driven by three laser pulses is investigated with time-dependent wave packet approach. Dependence of AT splitting on second laser pulse is studied. Photoelectron spectra show triple splitting with symmetric profiles in resonance, while triple splitting with asymmetric profiles is transformed into double splitting gradually in nonresnance. Three peaks shift to lower energy differently as laser wavelength increases. Splitting between two sideband peaks does not vary with laser wavelength, but increases with increasing laser intensity. These results are of importance for molecular spectroscopy. It stimulates theoretical studies from first principles and provides basis for realizing optical control of molecules.

Key words: time-dependent wave packet approach, four-level ladder K₂ molecule, photoelectron spectra, Autler-Townes splitting

中图分类号:

O644

李月华, 郭玮. 飞秒激光参数对四态阶跃型分子光电子能谱的影响[J]. 计算物理, 2016, 33(4): 453-459.

LI Yuehua, GUO Wei. Photoelectron Spectra of Four-Level Ladder Molecules: Effect of Femtosecond Laser Parameters[J]. CHINESE JOURNAL OF COMPUTATIONAL PHYSICS, 2016, 33(4): 453-459.

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