Field-free molecular orientation induced by combined femtosecond single-and dual-color laser pulses: The role of delay time and quantum interference  

作　　者：秦朝朝 贾光瑞 张现周 刘玉芳 龙金友 张冰 

机构地区：[1]Department of Physics, Henan Normal University, Xinxiang 453007, China [2]State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics,Chinese Academy of Sciences, Wuhan 430071, China

出　　处：《Chinese Physics B》2014年第1期201-205,共5页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China （Grant Nos. 61077037 and 11274096）, the Doctoral Research Fund of Henan Normal University, China （Grant No. qd 12109）, and the Key Scientific and Basic Technology Research Program of Henan Province, China （Grant Nos. 102102210184 and 122300410109）.

摘　　要：The coherent control of field-free molecular orientation of CO with combined femtosecond single- and dual-color laser pulses has been theoretically studied. The effect of the delay time between the femtosecond single- and dual-color laser pulses is discussed, and the physical mechanism of the enhancement of molecular orientation with pre-alignment of the molecule is investigated. It is found that the basic mechanism is based on the creation of a rotational wave packet by the femtosecond single-color laser pulse. Furthermore, we investigate the interference between multiple rotational excitation pathways following pre-alignment with femtosecond single-color laser pulse. It is shown that such interference can lead to an enhancement of the orientation of CO molecule by a factor of 1.6.The coherent control of field-free molecular orientation of CO with combined femtosecond single- and dual-color laser pulses has been theoretically studied. The effect of the delay time between the femtosecond single- and dual-color laser pulses is discussed, and the physical mechanism of the enhancement of molecular orientation with pre-alignment of the molecule is investigated. It is found that the basic mechanism is based on the creation of a rotational wave packet by the femtosecond single-color laser pulse. Furthermore, we investigate the interference between multiple rotational excitation pathways following pre-alignment with femtosecond single-color laser pulse. It is shown that such interference can lead to an enhancement of the orientation of CO molecule by a factor of 1.6.

关 键 词：molecular orientation femtosecond dual-color laser pulse quantum interference 

分 类 号：O[理学]