中文摘要：

利用飞秒激光超外差光Kerr（OHD-OKE）技术研究了As2S3,As2Se3,GeS2,GeSe2,Ge20 As25S55,Ge20 As25Se55,Ge10 As40S20Se30七个体系硫系非晶态半导体薄膜的三阶非线性性能,结果表明硫系非晶态半导体薄膜具有较大的三阶非线性极化率χ（3）值（达10-12esu）,非线性响应时间很快（小于200fs）.并根据测量结果计算出了薄膜的非线性折射率和吸收.硫系非晶半导体薄膜中较大的非线性极化率值的出现是由于核外电子轨道的非线性扭曲所致.

英文摘要：

Amorphous chalcogenide As2S3, As2Se3, GeS2, GeSe2, Ge20 As25 S55 , Ge20 As25 Se55 , Ge10 As40 S20 Se30 films were studied by femtosecond OHD-OKE. It was indicated that the third-order nonlinear susceptibility χ^ （3） was as large as 10^ -12 esu, and they also exhibited a very fast response time shorter than 200 fs. Their nonlinear refractive indices and absorption were also calculated from the above results. The ultrafast response and large third-order nonlinearity in amorphous chalcogenide films are attributed to the ultrafast distortion of the electron cloud of atoms.