Research on the mechanical stability of high laser resistant coatings on lithium triborate crystal.
The thermomechanical property of the hafnium/silica antireflection (AR) coatings on lithium triborate (LBO) crystal was investigated by simulation and experiment. From the analysis of the stress and fracture toughness, it was found that the crack originated due to the high tensile stress in hafnium coating. Then we proposed the approaches of decreasing the deposition temperature and substituting the hafnium layers with alumina to improve the mechanical stability of AR coatings on LBO crystals, and cracks were effectively suppressed. The laser damage threshold of different coatings on LBO crystal was tested, and it illustrated that the alumina/silica coatings possess better laser resistance than hafnium/silica AR coatings deposited in low deposition temperature.
Jinlong
J
Zhang
Xiaoqing
X
Bu
Bin
B
Ma
Hongfei
H
Jiao
Xinbin
X
Cheng
Zhanshan
Z
Wang