晶体中相干声子量子拍频的飞秒 TR －CARS研究

摘要

建立了利用飞秒TR－CARS技术研究晶体中相干声子动力学的理论模型，针对两个声子模式被同时激发时，它们之间相干耦合的量子拍频现象进行了数值模拟，讨论了两个声子模式的波数差、振幅因子之比以及失相时间变化对量子拍频曲线的影响。为在飞秒时间尺度上研究晶体中相干声子动力学提供了理论依据，对于理解相干声子的属性具有重要意义。%A theoretical model of studying the dynamics of coherent phonons in crystals was established by femtosecond TR -CARS technique , and the quantum beats of the simultane-ously excited two phonon modes were imitated .The influence on the curves of quantum beats when altering the parameters of the wavenumber difference , the ratio of amplitude actor and the dephasing times of the two phonon modes were discussed .This paper put forward a theo-retical basis to study coherent phonon dynamics in crystals on a femtosecond time scale , and was especially helpful for understanding the nature of coherent phonons .