基频HfO2/SiO2高反射薄膜激光损伤生长特性

摘要

以1064 nm波长作用下的HfO2/SiO2高反射薄膜为研究对象,研究了高反射薄膜在损伤生长过程中分层剥落初始损伤结构的变化规律、损伤形貌特征和损伤生长阈值等特性.实验结果表明:分层剥落初始损伤结构的横向尺寸随激光能量密度的增加呈分段线性增长,破斑沿纵向拓展的损伤生长阈值是沿横向拓展的损伤生长阈值的2倍以上,初始损伤结构横向尺寸的生长率与能量密度呈指数关系,且生长阈值随着辐照次数的增加显著降低.%The high reflection films will be damaged when irradiated by high power laser.With the increasing of the laser energy and the numbers of irradiation,the sizes of the initial damaged structure will grow,which has a serious effect on the application of the optics.In this paper,the varying rules,the damage feature and the damage growth threshold of the HfO2/SiO2 high reflection films under 1064 nm laser irradiation have been investigated.The results indicate that the lateral dimension of the delamination initial damage structure increases almost multi-linearly with the rise of laser fluence.The damaged growth threshold along the vertical expanding is more than twice as it along the horizontal expanding.In addition,the growth rate of the initial damaged structure grows with the rise of the laser fluence exponentially in the horizontal direction while the damage growth threshold decreases obviously with the rise of the shots.