基于量子拍的分子离解的研究  

Study on molecular dissociation based on quantum beatings

作　　者：朱长军[1] 翟学军[1] 薛兵[1] 贺俊芳[2] 

机构地区：[1]西安工程大学理学院,陕西西安710048 [2]中国科学院西安光学精密机械研究所瞬态光学与光子技术国家重点实验室,陕西西安710119

出　　处：《纺织高校基础科学学报》2010年第1期75-78,共4页Basic Sciences Journal of Textile Universities

基　　金：陕西省教育厅专项科研计划项目(08JK295);西安工程大学基础研究基金项目(XGJ07007)

摘　　要：为了研究Rb2分子离解的超快过程,分析了铷原子中两个耦合的参量四波混频过程,研究了量子拍随时间的演化.实验上利用泵浦-探测方法得到铷原子中参量四波混频信号随脉冲延迟的变化.结果表明,当2个耦合的参量四波混频过程的相位匹配达到平衡时,参量四波混频信号中可以观察到量子拍,量子拍幅度随时间的变化反映了由光聚合产生的分子的离解对激发的原子波包的影响.对参量四波混频时域信号进行含时傅立叶变换,得到了量子拍随时间的演化,从而提供了探测分子离解超快过程的方法,并进一步计算出了Rb2分子离解的时间.To investigate the ultrafast dissociation process in Rubidium dimmer, two coupled parametric fourwave-mixing processes in Rb atoms are analyzed and the quantum beating dynamics is studied. Pump-probe scheme is implemented experimentally to acquire the time varying four-wave-mixing signal in Rb. The results show that, when the phase matching conditions are fulfilled in the two parametric four-wave-mixing processes, quantum beating can be observed in the four-wave-mixing signal. The variation of quantum beating with time reveals the influence of the fragments from the dissociation of Rb2 on the excited atomic wave packets. Time-de- pendent Fourier transform is applied to process the time domain signal and the variation of quantum beating with time is obtained, hence an approach for detecting the ultrafast process in molecular dissociation is provided. Moreover, the Rb2 dissociation time is calculated.

关 键 词：非线性光学 参量四波混频 量子拍 分子离解 

分 类 号：O437[机械工程—光学工程]