1 064 nm与532 nm激光对电子束蒸发制备的HfO2/SiO2高反膜损伤比较

 研究了电子束蒸发制备的HfO₂/SiO₂高反膜在1 064 nm与532 nm激光辐照下的损伤行为。基频激光辐照时损伤形貌主要为节瘤缺陷喷溅留下的锥形坑，当能量密度较大时出现分层剥落；二倍频激光损伤主要是由电子缺陷引起的平底坑，辐照脉冲能量密度稍高时也会产生吸收性缺陷引起的锥形坑，但电子缺陷的损伤阈值更低；随着辐照脉冲能量密度的增大分层剥落逐渐成为主要的损伤形貌。分析认为，辐照激光波长的变化，引起吸收机制的变化从而导致了损伤阈值及损伤机制的差异。

Comparison of laser induced damage at 1 064 nm and 532 nm to high-reflective film fabricated by electron beam evaporation

The damage behaviors of HfO2/SiO2 high reflective optical thin film fabricated by electron beam evaporation (EBE) illuminated using 1 064 nm laser and 532 nm laser showed some difference. It was found that the damage was usually caused by absorptive defects and absorption near the interfaces under the irradiation of 1 064 nm laser, and the damage was caused by electronic defects and absorptive ones under irradiation of 532 nm laser and the former had lower damage threshold. Therefore, the key point to enhance the laser resistance of optical thin films at 1 064 nm was to prevent the presence of the absorptive defects, and to those at 532 nm was to eliminate the electronic defects．