LD Pump Single-Longitudinal-Mode Nd：GdVO4/RTP Solid-State Green Laser

The single-longitudinal-mode Nd：GdVO4/RTiOPO4 （RTP） solid-state Green laser operation of a laser-diode （LD） end-pumped laser is realized by multi-cavities and a Brewster plate. The LD-pumped single-frequency green laser has been demonstrated by optimizing several parameters and a cavity length, with precise temperature controlling of Nd：GdV04, RTP and laser diode. When the incident pump power is 2 W at 808.4 nm, a single-frequency cw green laser at 532nm with output 210 m W is obtained, the optical-to-optical conversion efficiency is up to 10.5%.     

等效可变孔径远场法测量单模光纤模场半径

本文提出等效远场的可变孔径方法,由测量光纤远场累积分布求得模场半径。并且利用Petermann关于模场半径的新定义,推出了一种对非高斯模场分布也适用的求模场半径的方法。实验表明,这种测量方法简便可靠,在不同的制备端面下,重复测量的标准误差小于0.04μm。     

激光痕量物证采集系统

Coherent（相干）公司推出独特而功能强大的新型Trac-ER^TM激光器，用于犯罪现场的痕量物证，包括隐约残留指纹的采集。TracER使用5W的绿光激光器。TracER的高输出功率大大提高了在犯罪现场进行无损搜索的效率，可以仅依据特征荧光采集指纹或其他痕量物证。同时，532nm波长非常适合于使用烟熏样品和荧光探针如茚三酮（ninhydrin）。     

Characteristics of Nd：GdVO4 Laser with Different Nd-Doping Concentrations

We report the properties of a compact diode-pumped continuous-wave Nd：GdV04 laser with a linear cavity and different Nd-doped laser crystals. In a 0.2at.% Nd-doped Nd：GdVO4 laser, 1.54 W output laser power is achieved at 912nm wavelength with a slope efficiency of 24.8% at an absorbed pump power of 9.4W. With 0.3at.% Nd-doping concentration, we can obtain the either single-wavelength emission at 1064nm or 912nm or the dual-wavelength emission at 1064nm and 912nm by controlling the incident pump power. From an incident pump power of 11.6 W, the 1064nm emission between ^4Fa/2 and ^4I11/2 is suppressed completely by the 912nm emission between ^4Fa/2 and ^4I9/2. We obtain 670 mW output of the 912nm single-wavelength laser emission with a slope efficiency of 5.5% by taking an incident pump power of 18.4 W. Using a Nd：GdV04 laser with 0.4at.% Nd-doping concentration, we obtain either the single-wavelength emission at 1064nm or the dual-wavelength emission at both 1064nm and 912nm by increasing the incident pump power. We observe a strong competition process in the dualavelength laser.     

激光准直仪的设计性物理实验

介绍了激光准直仪的结构、工作原理及其在设计性物理实验中的应用     

氧碘化学激光气固相化学反应体系热力学分析

氧碘化学激光器（COIL）的发展已经到了提高系统安全性和工作环境适应性、降低系统复杂性阶段，而改进O2（^1△g）的产生方式和方法正是这个阶段的重要工作内容之一。近期，美国空军研究实验室运用气-固相反应方式产生O2（^1△g）。采用碱金属过氧化物或碱土金属过氧化物与卤化氢反应，生成O2（^1△g）。通常气一固相反应有着反应速度慢，接触面积小，反应产物难以脱出固体表面的缺陷，使得产出率低，而不被广泛采用。但随着表面化学研究的突飞猛进，借助表面活化分子，特殊性质的表面构造，大表面的构造，都为气一固相反应的进行提供了可行途径。如果此方法能用在氧碘激光器上，将克服传统方法的诸多不足。     

High Power One- and Two-Order Cascaded Raman Lasers Based on Home-Made Phosphosilicate Fibre

One- and two-order cascaded Raman fibre lasers are demonstrated by using home-made P-doped Raman fibres.An output power of 2.8 W at 1245 nm with a slope efficiency of 33.4% and an output power of 2.0 W at 1495 nm with a slope efficiency of 23.5% are obtained with the pump source at 1069. 7nm.     

Antiphase State in Passively Q-Switched Yb：YAG Microchip Lasers with a Nd,Cr：YAG as Saturable Absorber

We experimentally investigate the antiphase dynamics phenomenon that occurs in a diode-pumped passively Q-switched Yb:YAG multimode laser with a Nd,Cr:YAG saturable absorber. Due to the effect of spatial hole burning, the multimode lasers with one, two, or three modes at different pump power are observed, and the pulses sequences display classic antiphase dynamics.