单次相关仪中非线性晶体KD*P的相位匹配条件分析

本文对应用于单次相关仪中的非线性晶体KD^*P的相位匹配条件进行了理论分析,得到了晶体的最佳相位匹配设计参数。利用此参数加工的非线性晶体已成功地用于测量超短光脉冲实验中,测得CPM Nd:YAG激光器输出的1.06μm光脉冲宽度为14ps.与条纹相机测量的结果二者符合较好。     

Amplified low-repetition-rate fs pulsewidth measuring and DLA caused pulse broadening

Amplified low-repetition-rate fs pulse is generated with dye laser amplifier(DLA). The pulsewidth is measured with a computer-aided autocorrelator and the fs pulsewidth broadening caused by the dispersion of the DLA is analyzed. Furthermore, the autocorrelator introduced in this paper could be used as a low scanning autocorrelator to measure high-repetition-rate pulsewidth.     

同步泵浦PML飞秒激光研究

采用CW锁模YAG倍频激光器同步泵浦PML飞秒染料激光器,产生了平均脉宽约55fs、功率为15mW的光脉冲。文章在理论和实验上还研究了同步泵浦飞秒激光脉冲产生技术。     

飞秒激光脉冲的谐波频率分辨光学开关法测量研究

建立了一台谐波频率分辨光学开关法(FROG)飞秒脉冲测量装置，利用该装置进行了掺钛蓝宝石飞秒激光脉冲的测量研究.在二次谐波自相关测得的时域和频域信号基础上，结合对信号光强度分布的计算机迭代处理，得到了有关飞秒激光电场、光谱及其相位的信息，所得脉宽与干涉测量的结果基本一致. 关键词： 频率分辨光学开关法(FROG) 迭代计算 飞秒激光 自相关     

飞秒激光扫描自相关仪

本文报道了一种测量飞秒激光脉冲宽度的扫描自相关仪,其扫描频率为25Hz,测量范围从20fs到900fs.采用的是BBO倍频晶体,测量光谱范围从700nm～1000nm.     

宽带自锁模钛宝石飞秒激光脉冲的实验研究

在线性Z形折叠腔的基础上,采用了一种能够消除输出耦合镜带宽限制的方法,用3mm的钛宝石短晶体和石英色散补偿棱镜得到了光谱带宽为121nm的自锁模钛宝石激光脉冲.在分析光脉冲自相关仪测量系统对测量影响的基础上,优化并基本消除了测量系统带来的影响,假设光脉冲形状为双曲正割型,得到了12fs的光脉冲,该光脉冲光谱半宽(FWHM)为87.6nm,中心波长为849.7nm,光脉冲平均输出功率为400mW,重复率为97MHz.     

二极管面阵侧泵浦Nd:YAG双板条激光器

叙述了二极管面阵侧泵浦双板条耦合单模模Ｑ开关激光器的研制。泵浦源为二极管面阵激光器,使用梯形波导板耦合系统,耦合效率达９０％,谐振腔为凸凹腔,全反射镜、的曲率半径为３．０ｍ的四面镜,输出镜为曲率半径３．０ｍ的可变反射率超高斯镜。激光器在１００Ｈｚ重复频率下,输出单脉冲能量１８．２３ｍＪ,脉宽为１５．２５ｕｓ,光束质量Ｍ２＜１．５具有平顶分布的超高斯光束。     

A GaAs/AlAs superlattice autocorrelator for picosecond THz radiation pulses

We report on a GaAs/AlAs, wide-miniband, superlattice autocorrelator for picosecond THz radiation pulses (operated at room temperature); the autocorrelator is based on the THz radiation-induced reduction of current through the superlattice. THz radiation (frequency 7.2 THz) from the FELIX (free-electron laser for infrared experiments) was coupled into the superlattice with an antenna system. We measured the current reduction for two time-delayed pulses and found that the signal decreased when the time delay was smaller than the pulse duration. With this superlattice autocorrelator we were able to resolve laser pulses that had a duration of a few picoseconds.     

一种激光驱动的超短X射线光源

介绍一种可产生超短脉冲的新型Ｘ射线光源。它由多碱光电阴极、金靶及铍输出窗组成，当该射线管的阴极受到强光照射时，产生光电子发射，并经电场加速后轰击金靶，产生连续谱的Ｘ射线轫致辐射，经铍窗输出。用超短的可见光脉冲驱动该光源，并借助Ｘ射线扫描相机测量了该管的Ｘ射线输出，获得了５ｐｓ的Ｘ射线脉冲，这种光源可方便地用来标定Ｘ射线扫描相机的时间分辨率，此种产生超短电子脉冲的方法可在其他方面获得应用。     

A parametric study of negative feedback Nd:YAG laser

The output pulse parameters of a mode-locked Nd:YAG laser with a passive negative feedback element were studied experimentally. The pulse evolution within the train was experimentally recorded using a modified second harmonic generation autocorrelator. By comparing the laser operation with and without an acousto-optic modulator, we found that with the later there is a significant increase in the mode locking probability and the pulse acquires a temporally Gaussian symmetric pulse shape. Further with the active modulator there is a relaxation in alignment tolerances and increase in the range of permissible dye concentrations for stable mode locking. It was also observed that the pulse width of the negative feedback laser depends on the saturation intensity of the mode locking dye and reduces for a dye with higher saturation intensity. The pulse width was also found to reduce linearly as the initial transmission of the dye is reduced.     

星光Ⅱ装置激光能量测量实时采集和数据传输系统

介绍一套激光能量实时采集和多路传输通信系统。该系统兼容现有的不同型号和规格的激光能量计,具有峰值保持和功率积分功能,抗干扰能力强,可实现数据自动采集、处理及长距离多点传送。为实现激光能量测量精密化和自动化打下了技术基础。     

LD调制有理数谐波锁模光纤激光器

本文将F-PLD与环形光纤激光器结合起来,以LD作为调制器,得到高稳定单波长超短光脉冲序列.与工作在增益开关状态的LD相比,平均输出功率提高到2mW,脉冲宽度压窄到47ps.并利用有理数谐波锁模技术,得到重复频率5GHz(5阶有理数谐波锁模)的锁模脉冲,脉冲宽度略有展宽为49ps.     

千赫重复率固体激光器可行性实验结果

本文介绍用Nd:YAG激光器进行输出千赫重复率激光脉冲可行性判断实验结果。间歇输出激光脉冲的指标为:重复率f=1700pps。激光能量E_L>100mJ/pulse。     

二极管泵浦自启动附加脉冲锁模Nd:YLF激光器

实现了激光二极管泵浦Nd:YLF激光器的自启动附加脉冲锁模,工作波长1053um,得到2.8ps的超短脉冲,重复频率130MHz,有效输出功率70mW.     

Adjusting pulse-front tilt and pulse duration by use of a single-shot autocorrelator

We present a method of adjusting the pulse duration and eliminating the pulse-front tilt of an ultrashort pulse in real time by use of a specially configured single-shot autocorrelator. Pulse-front tilt, or a temporal delay across the pulse front, is a common ultrashort-pulse phenomenon when dispersive elements are being used. We show the design of an autocorrelator that can be used to eliminate the pulse-front tilt and simultaneously adjust the pulse duration in real time by adjustment of the pulse compressor of a chirped-pulse amplified laser system.     

闪光灯泵浦的Nd:KGd(WO4)2激光器

报道了用闪光灯泵浦的掺钕的钨酸钆镓(Nd³⁺:KGd(WO₄)₂激光器.在重复频率1Hz,脉宽120μs的灯泵下,测量了不同透过率下激光输出能量,获得最大输出能量384mJ,斜率效率1.0%,外推阈值0.54J.在调Q运行时,Nd:KGW晶体的斜率效率为0.16%,最大输出能量46mJ.     

A rapid-scanning autocorrelation scheme for continuous monitoring of picosecond laser pulses

We describe a scheme for rapidly introducing a periodic linear time delay to a train of picosecond laser pulses. By incorporating this scheme in one arm of the Michelson interferometer of a conventional autocorrelator, the second order intensity autocorrelation function of a cw train of picosecond pulses is continuously displayed on an oscilloscope.     

利用非线性Sagnac干涉法提高短脉冲信噪比

理论研究了影响Sagnac干涉法信噪比提升能力和效率的各项因素。通过控制脉冲的空间分布和衰减片透过率,能够有效提高Sagnac干涉法的效率。Sagnac干涉法提升信噪比的能力与入射脉冲的信噪比有关:入射脉冲信噪比越高,信噪比提升的量级就越大。在SILEX-Ⅰ超短超强脉冲激光装置上建立了实验平台。3 TW压缩器输出的超短超强脉冲光经衰减片进入Sagnac干涉仪,非线性介质为5 cm长的熔石英材料,衰减片透过率为55%。当入射脉冲能量为6.6 mJ时,利用三阶自相关仪测量得到脉冲的信噪比从使用Sagna干涉仪前的10-6提高到了10-7,此时出射脉冲的能量为1.6 mJ,效率为24%。该方法对光束口径没有限制,能够用于大能量条件下短脉冲信噪比的提升。     

二极管侧泵浦单横模1kHz电光Q开关激光器

 本文介绍了二极管侧泵浦Nd:YAG板条1kHz重复频率Q开关激光器的研制,实验获得最大单脉冲能量0.712mJ,脉宽小于10ns的输出。对Nd:YAG板条进行了三种冷却方式的比较实验,实验证明DPL在高重复频率工作时,激光介质的热效应是影响高重复频率工作的激光器效率的重要因素。     

双光子开关的自相关函数

本文推导出半导体双光子光电导开关的自相关函数,给出对照比与激光强度的关系.实验测出GaAs在1.06 μm Nd:YAG激光超窄脉冲作用下的双光子自相关函数.