摘要
金属是组成超材料的重要成分,因此确定金属的表面二阶非线性系数对超材料非线性的研究十分重要。使用高灵敏度的光谱仪测量倍频信号,通过二阶非线性系数已知的石英晶体的Maker条纹对采集信号定标。实验上使用波长为800nm的飞秒激光为光源,系统地测量了入射角10°到80°范围内,不同偏振的飞秒激光入射到基于真空气相沉积镀制的35nm金薄膜上产生的倍频光强度,从而确定金膜的三个二阶非线性系数。实验测量数据与理论拟合一致。
Metal is an important component in building metamaterials.Therefore,it is very important to determine the surface second-order nonlinear susceptibility of metal in the study of metamaterial’s nonlinearity.A high-sensitive spectrometer was used to measure the second harmonic generation and the acquisition signal was calibrated by the Maker fringe of the quartz crystal whose second-order nonlinear susceptibility is known.Experimentally,a femtosecond laser with a wavelength of 800 nm was used as the laser source.The second harmonic signals generated from a 35 nm-thick gold film prepared by vacuum evaporation were systematically measured under different polarization conditions at incident angles from 10°to 80°.Then three second-order nonlinear susceptibilities of the gold film were determined.The experimental results are in good agreement with the theoretical calculation.
作者
吴萌
耿山楠
曹建军
钱维莹
高淑梅
刘诚
WU meng;GENG Shannan;CAO Jianjun;QIAN Weiying;GAO Shumei;LIU Cheng(School of Science,Jiangnan University,Wuxi 214122,China;Jiangsu Provincial Research Center of Light Industrial Optoelectronic Engineering and Technology,Wuxi 214122,China)
出处
《光学技术》
CAS
CSCD
北大核心
2021年第6期679-682,694,共5页
Optical Technique
基金
国家自然科学基金青年基金(61605067)
江苏省轻工光电工程技术研究中心(BM2014402)。
关键词
二阶非线性系数
Maker条纹
飞秒激光
金薄膜
second-order nonlinear susceptibility
maker fringe
femtosecond laser
gold film
