双调Q Nd:GdVO_4激光器的脉宽控制  

Control of the Pulse Duration in a Diode-Pumped Doubly Q-Switched Nd:GdVO_4 laser

作　　者：张海鹍[1] 席道明[1] 王静[1] 张中士[1] 赵圣之[2] 杨克建[2] 

机构地区：[1]济南大学理学院,山东济南250022 [2]山东大学信息科学与工程学院,山东济南250100

出　　处：《光学学报》2010年第3期797-801,共5页Acta Optica Sinica

基　　金：国家自然科学基金(60578010);济南大学科研基金(XKY0717);济南大学SRT资助课题

摘　　要：采用激光二极管(LD)抽运c轴切割的Nd:GdVO_4晶体,声光调制器作为主动调Q开关,Cr^(4+):YAG饱和吸收体作为被动调Q开关,实现了声光Cr^(4+):YAG主被动双调Q 1.06μm激光运转。实验结果表明,通过改变声光调制器和Cr^(4+):YAG饱和吸收体在谐振腔内的位置,可以有效地控制脉冲宽度,同时获得了双调Q激光的单脉冲能量、峰值功率的变化范围。根据ABCD矩阵传输理论计算得出的腔内模式半径沿腔轴的变化关系,考虑腔内振荡光强的空间高斯分布以及声光调制的渡越时间,给出了LD抽运声光Cr^(4+):YAG主被动双调Q激光的耦合速率方程组,理论计算与实验结果相符。By simultaneously using both active and passive Q-switched in the same cavity,a diode pumped doubly Qswitched c-cut Nd：GdVO_4 laser was realized with acoustic-optic（AO） modulator and Cr^（4＋）：YAG saturable absorber. The technique to control the pulse duration has been studied.With varying the positions of the saturable absorber and the modulator,the pulse durations are varied,respectively.The average output power,the pulse duration and the peak power versus the position were obtained.Using the ABCD matrix method,the intracavity radii along the cavity axis were calculated.Mean while,a rate equation model is introduced to theoretically analyze the results obtained in the experiment,in which the Gaussian spatial distribution of the intracavity photon density and the AO turnoff time including the transit time are taken into account.The numerical calculations of the rate equations,are consistent with the experimental results.

关 键 词：激光技术 激光二极管抽运 声光调Q开关 CR^4+:YAG 脉冲宽度 高斯分布 速率方程组 

分 类 号：TN248.1[电子电信—物理电子学]