The effect of an electric field on the thermomechanical damage of nodular defects in dielectric multilayer coatings irradiated by nanosecond laser pulses  

作　　者：Xinbin Cheng Jinlong Zhang Tao Ding Zeyong Wei Hongqiang Li Zhanshan Wang 

机构地区：[1]Key Laboratory of Advanced Micro-Structure Materials,Ministry of Education,Shanghai 200092,China [2]Institute of Precision Optical Engineering,School of Physics Science and Engineering,Tongji University,Shanghai 200092,China

出　　处：《Light(Science & Applications)》2013年第1期135-142,共8页光（科学与应用)（英文版）

基　　金：This work was partly supported by the National Natural Science Foundation of China(Grant Nos.61235011,61008030,61108014,61205124);the ChenGuang Project of Shanghai Municipal Education Commission(Grant No.10CG19);the Specialized Research Fund for the Doctoral Program of High Education(Grant No.20100072120037);the National 863 Program.

摘　　要：Thermomechanical damage of nodules in dielectric multilayer coatings that are irradiated by nanosecond laser pulses has been interpreted with respect to mechanical properties and electric-field enhancement.However,the effect of electric-field enhancement in nodular damage,especially the influence of electric-field distributions,has never been directly demonstrated through experimental results,which prevents the achievement of a clear understanding of the damage process of nodular defects.Here,a systematic and comparative study was designed to reveal how electric-field distributions affect the damage behavior of nodules.To obtain reliable results,two series of artificial nodules with different geometries and film absorption characteristics were prepared from monodisperse silica microspheres.After establishing simplified geometrical models of the nodules,the electric-field enhancement was simulated using a three-dimensional finite-difference time-domain code.Then,the damage morphologies of the artificial nodules were directly compared with the simulated electric-field intensity profiles.For both series of nodules,the damage morphologies reproduced our simulated electric-field intensity distributions very well.These results indicated that the electric-field distribution was actually a bridge that connected the nodular mechanical properties to the final thermomechanical damage.Understanding of the damage mechanism of nodules was deepened by obtaining data on the influence of electric-field distributions on the damage behavior of nodules.

关 键 词：electric field nanosecond-pulse-laser damage nodular defects thin films 

分 类 号：TG1[金属学及工艺—金属学]