双光子吸收材料用于高功率激光近场控制技术

 为了提高高功率激光光束质量和改善近场均匀性，在SILEX-Ⅰ超短脉冲激光装置的泵浦光系统上进行实验，研究了一种双光子吸收材料的光限幅特性及对激光近场的改善情况。利用泵浦光SAGA激光器输出的激光进行光限幅特性实验。结果表明:该材料具有明显的光功率限幅特性，且透过率较高，当入射光强小于0.60 GW/cm₂时，透过率大于90%。在SILEX-Ⅰ装置的泵浦光系统进行联机实验，研究了该材料对激光近场均匀性的改善。实验结果表明:经过材料后，激光近场均匀性和调制度有明显改善。

Improving near field of high-power laser beams using two-photon absorption material

Experiments have been conducted on the pumping system of the SILEX-Ⅰ ultra-short pulse laser facility to study the optical power limiting property of a two-photon absorption material and the improvement of near field uniformity using the material. The output laser beam from a flashlamp-pumped Nd:YAG laser SAGA was used to measure the optical limiting property of the material. The results show that the optical power limiting property is obvious. The transmission rate of the material is very high and it is greater than 90% when the input intensity is less than 0.60 GW/cm₂. Moreover online experiments done on the pumping system show that, modulation of near field spots is reduced greatly after the beam passes through the material and thus near field uniformity is improved.