熔石英损伤增长的复合波长效应研究

项目名称： 熔石英损伤增长的复合波长效应研究

项目编号： No.61505187

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 无线电电子学、电信技术

项目作者： 韩伟

作者单位： 中国工程物理研究院激光聚变研究中心

项目金额： 21万元

中文摘要： 高功率激光装置中熔石英元件同时承受多种波长激光的辐照，即波长分别为1053nm，527nm和351nm的基频光、二倍频光和三倍频光，由于复合波长效应的影响，熔石英在多波长辐照下的损伤增长行为不同于单一的紫外光辐照，其他波长激光对熔石英的紫外损伤增长存在一定的“加速”作用。我们前期研究发现，复合波长效应源于损伤过程中激光吸收的波长差异性，据此本项目提出从熔石英损伤的不同阶段来探索复合波长效应的产生机制，分析损伤过程中缺陷吸收、熔石英失控吸收以及等离子体吸收的波长差异性，获得具有一定理论基础的复合波长效应折算因子，并从实验上论证失控吸收的波长差异性；同时，研究复合波长辐照下熔石英的损伤增长规律，建立含复合波长效应的熔石英损伤增长模型。本项目研究结果有助于阐明复合波长效应的产生机制，对高功率激光装置熔石英使用寿命的精确预测和装置运行维护策略的科学设置具有重要意义，也可为激光损伤研究提供新的思路。

中文关键词： 激光损伤；；损伤增长；复合波长效应；熔石英

英文摘要： In high-power laser facilities, fused silica optics bear three laser irradiation simultaneously, which are fundamental light, second harmonic light and UV light with the wavelength of 1053nm, 526nm and 351nm respectively. Due to the multiple wavelengths effect, the damage growth behavior of fused silica under the irradiation of multiple wavelengths is different from that under the irradiation of single UV laser. Briefly, fundamental light and second harmonic light will strength the UV damage growth of fused silica. In our previous research, we found that the multiple wavelengths effect in damage growth of fused silica is closely related to the wavelength dependence of laser absorption in the damage process of fused silica. Thus we propose to explore the mechanism of multiple wavelengths effect from the wavelength dependence of laser absorption in the three main processes of laser damage, which are defects or impurities absorption, run-away absorption of fused silica and plasma absorption. We can obtain a converted coefficient with theoretical basis. Next we experimentally demonstrate the wavelength dependence of fused silica run-away absorption. Furthermore, we study the damage growth behavior of fused silica under the irradiation of multiple wavelengths, acquire the damage growth rule and build a damage growth model which contains the multiple wavelengths effect. The research results in this project will contribute to understanding the mechanism of the multiple wavelengths effect, and is significant in the accurate prediction of fused silica life and the operation and maintenance strategy design of laser facilities. It can also provide new idea for the laser damage research.

英文关键词： laser-induced damage ;damage growth;mulitple wavelengths effect;fused silica