ZnSe/SiO_2复合材料光学吸收特性的研究  

Optical Absorption Properties of ZnSe/SiO_2 Nanocomposites

作　　者：郝海燕[1] 姚熹[1] 万幸[1] 汪敏强[1] 吴小清[1] 

机构地区：[1]西安交通大学电子陶瓷与器件教育部重点实验室,西安710049

出　　处：《西安交通大学学报》2005年第12期1391-1395,共5页Journal of Xi'an Jiaotong University

基　　金：国家重点基础研究发展规划资助项目(2002CB613305)

摘　　要：采用溶胶-凝胶原位析晶法和高温还原热处理工艺制备了ZnSe/SiO2纳米复合材料.通过吸收光谱和Z-Scan技术对材料的光学吸收特性进行了表征.在吸收光谱中,不同ZnSe摩尔分数的样品的吸收边相对于ZnSe体材料发生了不同程度的蓝移,蓝移量与复合材料中ZnSe纳米晶粒的尺寸有关,根据量子尺寸效应估算了复合材料中ZnSe纳米晶粒的平均尺寸大约为3～4 nm. 利用Z-Scan技术测定了ZnSe摩尔分数为0.01和0.03的ZnSe/SiO2纳米复合材料的双光子吸收系数.ZnSe/SiO2纳米复合材料在不同强度的入射光的激发下其出射光强度与入射光强度之间的关系呈现光学限幅特征,ZnSe摩尔分数为0.01的样品的限幅阈值为5 962 GW/m2,嵌位输出值约为4 800 GW/m2,限幅的破坏阈值为12 400 GW/m2.ZnSe/SiO2 nanocomposites were prepared by sol-gel method and in-situ growth technique. The produced nanocomposites were characterized by ultraviolet visible spectrometry（UV-vis） absorption spectrum and Z-Scan technique. Compared to the ZnSe bulk materials, the absorption edge shifts to shorter wavelength in UV-vis spectrum of the nanocomposites. The shifts are closely related with the sizes of ZnSe nanocrystals. In term of the quantum size effect the average sizes of ZnSe nanocrystals were estimated about 3-4 nm. The two-photons absorption coefficients of nanocomposites with 0.01 and 0.03 molar fraction of ZnSe were obtained by Z-Scan system. Besides, the relation between the incidence laser intensity and the reflect laser intensity was investigated. The result shows itself optical limit properties. Of the samples of 0.01 molar fraction of ZnSe concerned, when the limitation threshold of input laser intensity is 5 962 GW/m^2, the clamping output intensity is 4 800 GW/m^2 , the output intensity keeps stable as the input intensity increases even more. The limit damage threshold of intensity is 12 400 GW/m^2.

关 键 词：ZnSe/SiO2纳米复合材料 光学吸收 光学限幅 

分 类 号：O437[机械工程—光学工程]