飞秒激光脉冲成丝过程中激射信号的实验研究  

The Investigation of Lasing Signal Generated During the Filamentation of Femtosecond Laser Pulse

作　　者：赵恒炜 张宇璇 林子钰 孙少华[1] 刘作业[1] ZHAO Hengwei;ZHANG Yuxuan;LIN Ziyu;SUN Shaohua;LIU Zuoye(School of Nuclear Science and Technology,Lanzhou University,Lanzhou 730000,China)

机构地区：[1]兰州大学核科学与技术学院,甘肃兰州730000

出　　处：《大学物理实验》2021年第2期41-47,共7页Physical Experiment of College

基　　金：兰州大学双一流拔尖人才培养-实践教学专项建设项目;兰州大学课程思政示范课程建设项目。

摘　　要：为了使理工科专业学生了解和应用飞秒激光技术,设计搭建了双色激光场泵浦-探测实验测量装置,采用高分辨光谱仪测量了飞秒激光成丝过程中N+2离子391 nm激射信号。通过对比圆偏振和线偏振的泵浦激光作用下的激射光谱,探究了391 nm激射产生的物理机制,观测了不同转动能级间跃迁的量子拍频现象,并提取了拍频信号的频率。In order to let college students majoring in science and engineering to know and use the femtosecond laser technology,an experimental setup basing on two-color laser fields in pump-probe configuration was designed and constructed,and the 391 nm lasing signal of N+2 ions during the filamentation of femtosecond laser pulse by applying a high-resolution spectrometer.The physical mechanism for the generation of the 391nm lasing was obtained by comparing the lasing spectra generated by the circular and linear polarized pump pulses.We also observed the quantum beating phenomenon of the transitions between different rotational energy levels,and the beating frequencies were extracted by performing Fourier transform to the time-dependent spectral lines.

关 键 词：激光成丝 等离子体成丝 激射效应 量子拍频 

分 类 号：O4-34[理学—物理]