高能量输出的皮秒Nd:YAG激光器的研究  

Investigation of a Picosecond Nd:YAG Laser with High Output Energy

作　　者：王加贤[1] 张文珍[1] 

机构地区：[1]华侨大学信息科学与工程学院,福建泉州362011

出　　处：《光电子．激光》2003年第2期127-130,共4页Journal of Optoelectronics·Laser

基　　金：福建省自然科学基金资助项目(A0010018);国务院侨办科研基金资助项目(02QZR04)

摘　　要：分别研究了2种闪光灯泵浦的高能量输出的皮秒Nd:YAG激光器。一种是Cr4+:YAG晶体作为可饱和吸收体,在强光作用下Cr4+:YAG的激发态吸收导致了激光器的被动锁模,获得能量25mJ、脉宽150ps的单脉冲序列,并从速率方程导出Cr4+:YAG激发态吸收的可饱和光强和小信号吸收系数;另一种是在折叠腔激光器内插入LiF:F-2晶体作为调Q器件、CS2作为克尔自聚焦介质,利用自聚焦和腔内合适位置的光阑相结合形成的克尔透镜效应,实现激光器在调Q包络下的锁模运转,输出激光能量达15mJ、脉宽为80ps。Two kinds of flashlamppumped picosecond Nd:YAG lasers with high output energy were investigated respectively.Firstly,Cr4+:YAG crystal was used as a saturable absorber.The excitedstate absorption saturation of the Cr4+:YAG crystal under the action of strong laser pulses results in the passive modelocking operation of the Nd:YAG laser.A single pulse train with the energy of 25 mJ and the pulse duration of 150 ps was obtained.The saturable light intensity and the smallsignal absorption coefficient for the excitedstate absorption of Cr4+:YAG crystal were theoretically deduced from the rate equations.Secondly,LiF:F-2 crystal was inserted in the folded cavity as a Qswitch device and CS2 was used as a kerrselffocusing medium.The modelocking in a Qswitched envelope of the Nd:YAG laser was realized using the kerrlens effect formed in combination with selffocusing and an aperture at a specific site in the cavity.The output energy and pulse duration are 15 mJ and 80 ps respectively.

关 键 词：ND:YAG激光器 被动锁模 克尔透镜效应 CR^4+:YAG晶体 吸收体 

分 类 号：TN248.13[电子电信—物理电子学]