摘要
针对神光Ⅱ第九路激光装置三倍频达标实验中出现的大口径融石英玻璃的破坏现象,分析产生的原因和机制,确定了是由横向受激布里渊散射(TSBS)造成的,并采用了有效抑制TSBS的方案。理论上建立了大口径融石英玻璃中横向受激布里渊散射的增益模型,利用该模型计算了高功率激光系统中融石英取样镜的破坏阈值。实验结果和理论计算均得到310 mm口径窄带激光能量达到2～3 kJ时融石英玻璃将产生破坏。
Damage of a sampling fused silica reflector has been observed when the performance of the 9th beam of Shenguang- Ⅱ was tested. By analyzing the inducement and mechanism,it is confirmed that the transverse stimulated Brillouin scattering （TSBS） induces the damage. Increasing the bandwidth by 30 GHz can prevent further damage efficiently. A propagation model of TSBS in large aperture fused silica has been established, which can calculate the intensity threshold of laser induced damage in fused silica, Theoretical calculation and experimental results show that the fused silica glass will be damaged if the energy of large aperture（310 mm diameter） narrow bandwidth laser reaches 2-3 kJ.
出处
《光学学报》
EI
CAS
CSCD
北大核心
2009年第3期756-760,共5页
Acta Optica Sinica
关键词
受激布里渊散射
破坏阈值
增益模型
融石英
stimulated Brillouin scatlering
damage threshold
gain model
fused silica
