二束飞秒脉冲对O2分子转动波包的适时控制  

Adaptive Manipulation of Rotational Wave Packets for O_2 Molecules by Two Femotosecond Pulses

作　　者：杨增强[1] 郭志荣[1] 张建军[1] 

机构地区：[1]石河子大学师范学院物理系／石河子大学生态物理重点实验室,石河子832003

出　　处：《石河子大学学报（自然科学版）》2010年第4期519-523,共5页Journal of Shihezi University(Natural Science)

摘　　要：为了确定最佳延迟时间,更加有效控制分子转动波包。通过数值求解O2分子在脉冲激光作用下的薛定谔方程,研究了O2分子在飞秒激光作用下的转动波包特征。计算结果表明,在分子转动波包的第1个恢复周期附近,根据取向参数变化率,加上具有恰当延迟时间的第2束激光脉冲,能极大地提高分子取向,从而改变波包的转动特征;同样,在分子转动波包的二分之一恢复周期附近,根据取向参数变化率,加上具有恰当延迟时间的第2束激光脉冲,能极大地降低分子取向,从而有效抑制分子转动波包。在激光强度不变的情况下,只要同时改变二束激光的脉冲宽度,适时控制延迟时间,能进一步提高分子取向,从而有效控制分子转动波包。By solving time-dependent Schrdinger equation numerically,field-free alignment of O2 molecule induced by femotosecond laser pulse is researched in order to control the molecular rotational wave packet effectively.The results show that the alignment parameter can be enhanced intensively when inserting the peak of the second laser pulse at the time while a local maximum of the slope for the alignment parameter locates around the full revival,and the alignment by the first laser can be degraded when inserting the peak of the second laser pulse at the time while a local minimum of the slope for the alignment by the first laser locates around the half revival.What’s more,the alignment can be further increased by optimizing the pulse duration of the two lasers as well as the optimized time delay on the condition that the two laser intensity is fixed.

关 键 词：脉冲激光 分子取向 脉冲宽度 

分 类 号：O434.13[机械工程—光学工程] Q682[理学—光学]