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利用可饱和吸收半导体GaAs作为被动调Q元件和FP输出耦合镜,实现了半导体激光器(LD)抽运Nd:YVO4激光调Q运转,获得脉宽度为47ns,重复频率为1183kHz,平均功率为430mW,光束质量为M2=113的TEM00激光基横模输出,调Q抽运阈值为1700mW.并数值求解了含有GaAs被动调Q兼输出耦合的速率方程,分析了GaAs被动调Q机理以及脉宽宽度、重复频率、平均功率随抽运速率、腔长的变化关系,理论与实验结果相一致.为多功能综合型微型调Q固体激光器提供了简单有效的方法.
关键词:
被动调Q
输出耦合
GaAs 相似文献
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We presented a novel orthogonally linearly polarized Nd:YVO4 laser. Two pieces of a-cut grown-together composite YVO4/Nd:YVO4 crystals were placed in the resonant cavity with the c-axis of the two crystals orthogonally. The polarization and power performance of the orthogonally polarized laser were investigated. A 26.2-W orthogonally linearly polarized laser was obtained. The power ratio between the two orthogonally polarized lasers was varied with the pump power caused by the polarized mode coupling. The longitudinal modes competition and the corresponding variable optical beats were also observed from the orthogonally polarized laser. We also adjusted the crystals with their c-axis parallele to each other, and a 40.7-W linearly polarized TEM00 laser was obtained, and the beam quality factors were M2x=1.37 and M2y=1.25. 相似文献
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Laser multi-layer cladding on ZM6 magnesium base alloy 总被引:2,自引:0,他引:2
A pulsed Nd: YAG laser is used in multi-layer cladding on ZM6 Mg base alloys. The microstructure is studied with an optical microscope and a scanning electron microscope (SEM). The composition within the layer was determined by electron probe microanalysis (EPMA). X-ray diffraction (XRD) was also used to investigate the phase of constitutes of the cladding zone. The results show that microstructure in solidified cladding layer changes much when treated by high energy laser beam. The microstructure of the ZM6 alloy consists of a-Mg and Mg9Nd, while the L-ZM6 of a-Mg, MggNd and a-Zr. The depth of the cladding is over 1 mm. Many fine particles were found to be distributed homogeneously throughout the matrix and the columnar grain grows along substrate. 相似文献
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在任意三角形内,三边中点,三高的垂足,以及连接顶点与垂心的三线段的中点,都在同一圆上,此圆即为三角形九点圆.三角形的九点圆是欧氏几何中著名的优美定理,被称为欧拉圆和费尔巴哈圆.本文试图把垂心改换为平面内的任意点,相应地把三条高线改换为过每个顶点各一条的共点直线组时,则将把三角形的九点圆有趣地推广为三角形的九点二次曲线.并具体讨论在不同的区域内得到的九点二次曲线. 相似文献
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一.引 言 谱分析是物理学的一个重要内容.在光谱学、电子顺磁共振波谱学、核磁共振波谱学、无线电物理、音响与振动等等物理学领域里都要进行谱分析.傅里叶变换一直是谱的理论分析依据.随着数字计算技术的发展,1965年 Cooley和Tukey提出了快速傅里叶变换(FFT)方法[1],使离散傅里叶变换的复数乘法运算次数由N2次减小到(N/2)log2N次,大大降低了运算量,提高了运算速度,可以用数字计算机实现傅里叶谱分析了.FFT技术应用到上述诸领域,出现了傅里叶光谱学、脉冲傅里叶核磁共振波谱学等新分支;在实验技术上出现了傅里叶光谱仪、脉冲傅里叶核磁… 相似文献
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主要研究了一类带有分布时滞的自治的生态传染病模型,得到了使得系统持久尤其是染病者持久的充分条件. 相似文献