Nonlinear Optical Properties of Al-Doped nc-Si-SiO_2 Composite Films  

掺Al的纳米Si-SiO_2复合薄膜的光学非线性特性(英文)

作　　者：郭亨群[1] 杨琳琳[1] 王启明[2] 

机构地区：[1]华侨大学信息科学与工程学院,泉州362011 [2]中国科学院半导体研究所,北京100083

出　　处：《Journal of Semiconductors》2007年第5期640-644,共5页半导体学报（英文版）

基　　金：国家自然科学基金资助项目(批准号:60336010)~~

摘　　要：The nonlinear optical properties of Al-doped nc-Si-SiO2 composite films have been investigated using the time-resolved four-wave mixing technique with a femtosecond laser. The off-resonant third-order nonlinear susceptibility is observed to be 1.0 × 10-10 esu at 800nm. The relaxation time of the optical nonlinearity in the films is as short as 60fs. The optical nonlinearity is enhanced due to the quantum confinement of electrons in Si nanocrystals embedded in the SiO2 films. The enhanced optical nonlinearity does not originate from Al dopant because there are no Al clusters in the films.采用时间分辨四波混频方法,用钛宝石飞秒激光器测量了掺Al的纳米Si-SiO2复合薄膜的光学非线性特性.得到薄膜非共振三阶非线性极化系数为1·0×10-10esu,弛豫时间为60fs.分析认为薄膜的光学非线性增强来源于SiO2镶嵌的纳米Si中电子的量子限制效应,而不是来源于Al杂质,这是因为Al易被氧化,薄膜中没有形成Al团簇.

关 键 词：Si nanocrystals composite films third-order nonlinearity time-resolved four-wave mixing 

分 类 号：O437[机械工程—光学工程]