室温下连续波运行Tm:YAP泵浦的Ho:YAG激光器

我们报道了一种以二极管泵浦的 1.94 μm Tm:YAP激光器为泵浦源，常温下在2.1 μm连续运行的Ho:YAG激光器。最大输出功率1.5 W，相应斜率效率为17.9%，二极管到的转换效率为5.6%。

Campagne Chalci 80-01 (20/8/1980-10/9/1980): résultats des chalutages

One additional Chalci campaign that, in line with the previous Chalci campaigns 78-01, 78-02, and 79/01, has as its major objective the trawl exploration of the Ivoirian continental shelf at the depth of 10 to 120 metres.

提拉法Tm：YAG晶体的生长缺陷研究

采用提拉法(CZ)生长了质量优异的Tm：YAG晶体．部分晶片在1000℃的空气气氛中退火25h．借助光学显微镜、扫描电子显微镜(SEM)，结合化学腐蚀法，对Tm：YAG晶体退火前后(111)面的缺陷特征进行了研究．Tm：YAG晶体(111)面的位错腐蚀坑呈三角形．在偏光显微镜下观察了退火前后Tm：YAG晶体(111)面的应力双折射．同时应用高分辨X射线衍射法测定了晶体的完整性．实验结果表明，长时间空气气氛下高温退火有效降低了晶体中总的位错密度，提高了晶体质量．

Tm：YAG晶体的研究进展

Tm：YAG晶体是性能优异的LD泵浦激光晶体。本文总结了Tm：YAG晶体的生长、光谱性质以及激光性能的研究和发展，并指出了Tm：YAG晶体发展中需要解决的问题。

Infrared to visible upconversion fluorescence in Yb,Tm : YAG single crystal

Absorption spectrum from 400 to 2000 run and upconversion fluorescence spectra under 940 nm pumping of YAG single crystal codoped with 5 at.% Yb3+ and 4 at.% Tm3+ were studied at room temperature. The blue upconversion emission centered at 483 nm corresponds to the transition (1)G(4) -> H-3(6), the emission band around 646 nm corresponds to the transition (1)G(4) -> F-3(4) of Tm3+. Energy transfer from Yb3+ to Tm3+ is mainly nonradiative and the transfer efficiency was experimentally assessed. The line strengths, transition probabilities and radiative lifetimes of (1)G(4) level were calculated by using Judd-Ofelt theory. Gain coefficient calculated from spectra shows that the upconversion corresponding with transitions (1)G(4) -> H-3(6) in YAG doped with Yb3+ and Tm3+ is potentially useful for blue light Output. (c) 2006 Elsevier B.V. All rights reserved.

室温下光纤耦合二极管泵浦Tm：YAP激光器

为实现室温下小型化、高效率的1.9μm激光输出,采用793.5 nm激光二极管泵浦Tm：YAP晶体,晶体采用热电制冷及风冷的方式控制在18℃,采用1∶1的聚焦耦系统,获得功率为2.2 W、中心波长为1928 nm的激光输出,光光转换效率为31%,斜率效率达41%。对影响激光输出的耦合输出率、腔型、腔长、晶体工作温度等因素进行了实验分析,实验结果表明：输出功率的变化与温度基本成线性关系,当增加激光谐振腔长时,由于高阶模式损耗加大以及晶体热透镜效应的加重导致腔内损耗加大,输出功率和斜率效率都有所下降。

激光二极管抽运Tm：YAP激光器获得5W连续波输出

2μm波长激光对人眼安全，在相干探测风切变、非线性频率转换等方面有重要应用。2μm波长激光还可应用到激光医疗，由于其吸收深度浅，手术精度高于发射1μm波长的激光。

高效室温下激光二极管泵浦Tm:YAP激光器

文章报道了室温下二极管泵浦Tm：YAP激光器，最大输出功率5.2瓦，波长为1981nm，斜率效率是30％。实验测量800nm左右晶体的吸收谱以及1800nm附近的荧光发射谱。此外，讨论了输出功率随晶体工作温度关系。

Growth and spectral properties of Yb,Tm:YAG crystal

The YAG crystal codoped with Yb3+ and Tm3+ has been grown by Czochralski (Cz) method. The crystal structure of the crystal has been determined by X-ray diffraction analysis. The absorption and emission spectra of Yb,Tm:YAG crystal at room temperature have also been studied. The emission cross-sections have been calculated by Fuechtbauer-Ladenburg formula and reciprocity method. (C) 2007 Elsevier B.V. All rights reserved.

Room-temperature cw and pulsed operation of a diode-end-pumped Tm:YAP laser

We report the continuous-wave and acousto-optical Q-switched operation of a diode-end-pumped Tm:YAP laser. Continuous-wave output power of 3.5 W at 1.99 mu m was obtained under the absorbed pump power of 14 W. Under Q-switched laser operation, the average output power increased from 1.57 W to 2.0 W, with an absorbed pump power of 12.6 W, as the repetition rate increased from 1 kHz to 10 kHz. The maximum Q-switched pulse energy was 1.57 mJ with a repetition rate of 1 kHz. The minimum pulse width was measured to be about 80 ns, corresponding to a peak power of 19.6 kW.