Effect of native defects and laser-induced defects on multi-shot laser-induced damage in multilayer mirrors

• 来源期刊: 中国光学快报（英文版）
• 年，卷（期）: 2011,（9）
• 页码范围: 82-85
• 页数: 4页
• 语种: 英文
• DOI: 10.3788/COL201109.093102.

摘要

The roles of laser-induced defects and native defects in multilayer mirrors under multi-shot irradiation condition are investigated.The Hf02/SiO2 dielectric mirrors are deposited by electron beam evaporation (EBE).Laser damage testing is carried out on both the 1-on-1 and S-on-1 regimes using 355-nn pulsed laser at a duration of 8 us.It is found that the single-shot laser-induced damage threshold(LIDT)is much higher than the multi-shot LIDT.In the multi-shot mode,the main factor influencing LIDT is the accumulation of irreversible laser-induced defects and native defects.The surface morphologies of the samples are observed by optical microscopy.Moreover,the number of laser-induced defects affects the damage probability of the samples.A correlative model based on critical conduction band(CB)electron density(ED)is presented to simulate the multi-shot damage behavior.