摘要
采用Maker条纹测试方法,首次在电场-温度场极化GeS2-Ga2S3-PbI2准三元体系硫卤玻璃中观察到了明显的二次谐波发生(SHG).对于70GeS2·15Ga2S3·15PbI2组分玻璃,详细研究不同极化电压、极化温度和极化时间对二次谐波(SH)强度的影响,发现当极化温度高于190℃,电压高于4·0kV时,可以观察到SHG并且SH强度随极化电压与时间的升高而增大直至饱和.在6kV极化40min的条件下,SH强度随极化温度的升高先增大后减小.在6kV、250℃、40min的最佳极化条件下,70GeS2·15Ga2S3·15PbI2玻璃的二阶非线性极化率χ(2)达到最大值4pm·V-1.根据偶极子取向模型,讨论了二次谐波效应的机理是该硫卤玻璃中偶极子在高温条件下摆脱网络束缚沿外加电场方向取向调整,从而破坏了玻璃的宏观各向同性所致,并定性解释了极化条件对玻璃二阶光学非线性效应的影响.
Utilizing Maker fringe method, second-harmonic generation （SHG） was observed from electrically poled chalcohalide glass in a GeS2-Ga2S3-PbI2 pseudo-ternary system for the first time. The 70GeS2 ·15Ga2S3＂ 15Pbi2 composition glass was poled by applying various high dc voltages at various temperatures for different poling durations. SHG was observable from 19012 under 4.0 kV, and the second harmonic （SH） intensity increased with the enhancement of applied voltage and poling duration until reached saturation. When conducted under 6 kV for 40 min, with increasing poling temperature the SH intensity gradually increased, experienced a maximum, and then decreased. A maximum second-order nonlinearity susceptibility, Z（2）, value of 4 pm· V^- 1 was obtained under the optimal poling condition of an applied voltage of 6 kV, a temperature of 250℃ and a poling duration of 40 min. The SHG phenomenon is considered to be the result of the breakage of glassy macroscopic isotropy originated from reorientation of dipoles during electrical poling treatment and the dependence of poling parameters on the SH intensity is also discussed.
出处
《北京科技大学学报》
EI
CAS
CSCD
北大核心
2007年第2期151-156,177,共7页
Journal of University of Science and Technology Beijing
基金
国家自然科学基金资助项目(50125205)
硅酸盐材料工程教育部重点实验室(武汉理工大学)开放基金资助项目(SYSJJ2005-13)
关键词
硫卤玻璃
二阶非线性光学效应
电场极化
温度场
二次谐波
chalcohalide glass
second-order optical nonlinearity
electrical poling
temperature field
second harmonic
