(Au,Ag,Cu)/SiO₂二元金属单分散复合薄膜非线性光吸收性的Mie理论模拟

来源期刊：金属学报2011年第2期

论文作者：严丽平 张波萍 王士京 赵翠华 李顺

文章页码：203 - 208

关键词：Mie理论； (Au,Ag,Cu)/SiO₂复合薄膜； 非线性光吸收

Key words：Mie theory； (Au,Ag,Cu)/SiO₂ nano-composite film； nonlinear optical absorption spectra

摘    要：采用修正的Mie理论模拟计算了(Ag,Cu)/SiO₂,(Au,Cu)/SiO₂和(Ag,Au)/SiO₂二元单质金属纳米颗粒分散体系的理论吸收光谱.研究发现,二元金属纳米颗粒分别以单质金属形式存在时,吸收光谱分别在2个波段处出现表面等离子共振吸收峰,二元金属的相对含量影响吸收峰的峰强,与峰位无关.理论模拟吸收光谱与前人实验结果符合良好.

Abstract: Due to the surface plasmon resonance (SPR) and enhanced local field effect of metal particles,nano-composite films exhibit a variety of properties,such as large third order nonlinear susceptibility,superfast response time and absorption peaks in the optical spectra at a special wavelength.Therefore they are attractive candidates for optical communication,such as information storage and optical device.In recent years,the metal nanoparticle nonlinear optical composite films have been developed rapidly,expanded from single metal nano particle dispersion system to the dual metal nano particle dispersion system.However,theoretical study on the nonlinear optical absorption of the dual metal nano particle dispersion system is quite rare.In this study,the optical absorption spectra of the (Ag,Cu)/SiO₂,(Au,Cu)/SiO₂ and (Ag,Au)/SiO₂ binary metals dispersed nano-composite films were simulated by modified Mie theory.When the metal particles with a low full factor are smaller than the incident wavelength in diameters,the optical spectra of (Ag,Cu)/SiO₂,(Au,Cu)/SiO₂ and (Ag,Au)/SiO₂ composite films in which the nanoparticles solely dispersed in each metal state,can be calculated and analyzed based on the modified Mie theory using the optical parameters of the component.Two SPR absorption peaks appear in the corresponding wavelength of the single metal dispersed nano-composite films. The intensities of SPR absorption peaks depend strongly on the relative content of binary metals, while their peak positions are constant regardless of the content.The calculated optical absorption spectra by proposed method in this study are in good agreement with the reported experiment results. It suggests that the linear superposition method is feasible to calculate the absorption spectra of other separated binary and/or multiplex metals dispersed nano-composite films.