Absorption modification by laser irradiation in DKDP crystals

• 来源期刊: 中国光学快报（英文版）
• 年，卷（期）: 2018,（5）
• 页码范围: 66-69
• 页数: 4页
• 语种: 英文
• DOI: 10.3788/COL201816.051601

摘要

Laser-induced modification at 355 nm of deuterated potassium dihydrogen phosphate (DKDP) crystals follow-ing exposure to nanosecond (ns) and sub-ns laser irradiation is investigated in order to probe the absorption mechanism in damage initiation. Laser damage resistance is greatly improved by sub-ns laser conditioning, whereas only a little improvement occurred after ns laser conditioning at the same laser fluence. Moreover, scat-tering and transmittance variations after the two types of laser conditioning indicate similar reduction of linear absorption. However, by contrast, large differences on nonlinear absorption modification are discovered using Z-scan measurement. This characteristic absorption modification by laser irradiation provides evidence that a nonlinear absorption mechanism plays a key role in damage initiation at 355 nm.