真空环境中紫外脉冲激光对熔石英抗损伤能力的影响

在10-3Pa的高真空环境下,利用355nm的紫外脉冲激光以低于石英基片零概率损伤阈值的能量密度对其进行重复多次的全口径扫描,目的是为了研究石英基片在接受不同剂量的紫外激光辐照后其抗损伤能力的变化和原因.通过辐照过程中损伤点的扩展程度以及辐照后的抗损伤测量表明,高真空环境下紫外脉冲激光辐照后的石英基片抗损伤能力明显降低,降低的幅度更多的与其接受激光辐照的次数有关,辐照能量密度的影响相对较小;通过荧光及X射线光电子能谱(XPS)检测发现,紫外脉冲激光辐照后石英基片表面氧缺位的增加是导致其抗损伤能力下降的主要原因,其程度也直接与接受辐照的紫外脉冲激光剂量相关.

Influence of ultraviolet pulse laser irradiation on fused silica anti-damage ability in high vacuum environment

In high vacuum environment of 10^-3 Pa, using 355 nm pulsed ultraviolet(UV) laser we repeatedly raster scanning fused silica at energy density of under zero probability damage threshold, with the purpose of studying the change in anti-damage ability of fused silica after receiving different UV laser irradiation dosages in high vacuum. The damage measured after irradiation and increasing of damage pit indicate that the anti-damage ability of fused silica obviously drop, the degree of depression is more closely correlated with the irradiation time, while the influence of irradiation energy density is weak. The measurement of fluorescence excitation and X-ray photoelectron spectros copy proves that the increase of oxygen-deficiency in fused silica is the main cause, and the degree correlates with the received UV laser irradiation dosage.