激光二极管抽运氦气冷却钕玻璃叠片激光放大器热致波前畸变和应力双折射的数值模拟和实验研究

热效应仍是限制激光放大器向高功率、高光束质量进一步发展的瓶颈问题, 高效的热管理是抑制热效应的重要技术途径. 研究了基于激光二极管抽运氦气冷却的钕玻璃叠片激光放大器的热效应. 利用有限元数值模拟的方法, 分析了钕玻璃的温度、应力应变和应力双折射分布, 并计算了热致波前畸变和退偏损耗, 与实验结果符合得较好, 在热沉积为0.7 W/cm³的条件下, 6片钕玻璃总的热致波前畸变为6.77λ , 最大退偏量大于90%.     

激光二极管抽运的高重频高平均功率Nd:YAG激光器

搭建了一台高重复频率、高峰值功率、高平均功率的激光器. 激光器主要包括三部分: 单纵模光纤种子源、激光二极管阵列抽运的Nd:YAG再生放大器和四程放大器. 系统获得了平均功率11 W、重复频率100 Hz、脉冲能量112 mJ、脉宽500 ps–2 ns可调的激光输出, 工作波长1064 nm. 输出光束口径6.8 mm, 1.5倍衍射极限, 近场光强近平顶分布, 能量稳定性为0.72%. 关键词： 激光二极管抽运 高重复频率 高峰值功率 高平均功率     

Optimization of Pulse Temporal Contrast in Optical Parametric Chirped Pulse Amplification

In optical parametric chirped pulse amplification （OPCPA）, the degradation of temporal contrast of the compressed signal pulse mainly results from spectral clipping in the grating stretcher with finite size of the optics, parametric fluorescence （PF） and the spectral variations transferred from temporal fluctuation of the pump pulse. The temporal contrast of the recompressed amplified pulse in the OPCPA system is studied numerically and a number of solutions are considered and optimized to achieve the highest temporal contrast.     

高功率激光装置前端系统激光脉冲的时间整形及修正技术

针对激光惯性约束聚变实验研究对高功率激光驱动器前端系统复杂时间形状种子激光脉冲的需求,应用孔径耦合带状线集成波导整形系统设计了满足需要的前端整形激光脉冲。用一种新方法精确计算了孔径耦合带状线电脉冲整形器的耦合系数和孔径宽度的数值关系,并针对高衬比度整形激光脉冲的需求,提出了高衬比度双极型集成波导整形系统方案。由该系统可以得到100 ps脉冲前沿、1～3 ns脉冲宽度可调、高衬比度(大于100:1)、光滑无纹波调制、可精确满足神光Ⅱ八路及第九路装置需求的前端整形激光脉冲。     

反相高效液相色谱法的多波长同时测定预混合饲料中的脂溶性维生素A，α－E，D_3，K_3

反相高效液相色谱法的多波长同时测定预混合饲料中的脂溶性维生素Ａ，α－Ｅ，Ｄ＿３，Ｋ＿３李桂凤，李缙扬，郝征红，聂燕，孟兆宏，李学春（山东省农业科学院中心实验室济南２５０１００）１前言对脂溶性维生素的分析，被许多国内外分析专家认为是高难度的分析项目。本...     

Theoretical and experimental research on cryogenic Yb:YAG regenerative amplifier

Based on the theory of quasi-three-level rate equations modified by amplified spontaneous emission,the stored energy density and the small signal gain of the cryogenic Yb:YAG regenerative amplifier for a given geometry for pulsed pumping in three dimensions are theoretically studied using the Monte Carlo simulation.The present model provides a straightforward procedure to design the Yb:YAG parameters and the optical coupling system for optimization when running at cryogenic temperature.A fiber-coupled laser diode end-pumped cryogenic Yb:YAG regenerative amplifier running at 1 030 nm is demonstrated with a maximum output energy 10.2 mJ at a repetition rate of 10 Hz.A very good agreement between the experiments and the theoretical model is achieved.     

Highly Stable, Diode-Pumped Nd：YLF Regenerative Amplifier

We present the design and experimental results for a diode pumped Nd：YLF regenerative amplifier applied to amplify a nanosecond laser pulse. Numerical simulation shows that the maximum output energy and the best stability can be obtained when the regenerative amplifier operates in a saturated mode for all pulse duration and temporal profiles. Using extra post-pulse is a good method to decrease the square-pulse distortion caused by gain saturation effect. The amplifier shows output energy of 4.2mJ with a total energy gain of more than 10^7 and output energy stability of better than 1% rms. When extra post-pulse is added, square-pulse distortion is decreased from 1.33 to 1.17 for the amplifier that is seeded with an optical pulse of 3ns.     

High-efficiency hybrid brillouin/ytterbium fiber laser

A high-efficiency hybrid Brillouin/ytterbium fiber laser (BYFL) is demonstrated using a 41.5-cm-longhighly ytterbium-doped fiber and a 10-m-long single-mode optical fiber. The BYFL operates at 1 052.92nm, and the difference between it and the Brillouin pump (BP) wavelength matches the expected stimulated Brillouin scattering (SBS) Stokes shift. Its output power reaches 70.1 mW, which is more than seven times higher than the seeded BP power. The BYFL has an optical signal-to-noise ratio that is greater than 65 dB and has many potential applications, such as in controllable optical delay lines, sensing, and RF photonics.     

Yb3+相移分布反馈光纤激光器的理论分析

对相移分布反馈掺Yb^3 光纤激光器进行了理论分析，发现当相移为π时，增益阈值最小，相移越远离π，增益阈值越大，信号波长越偏离布拉格波长；随着光纤光栅耦合系数的增加，激光器的增益阈值越小，输出功率越大；相移分布反馈光纤激光器的正向和反向输出持性与光纤光栅的相移点的位置有关。     

影响相移光纤分布反馈激光器的增益阈值的因素

本文从理论上分析了在光纤光栅的调制度一样的情况下,影响光纤分布反馈激光器的增益阈值的几个因素:相移量的大小,相移区的长度以及相移区在光纤光栅中的位置.