亚波长金属柱阵列光透射增强的带通特性研究

Study on band-pass characteristics of the enhanced optical transmission of subwavelength metal column array

为了研究玻璃衬底上的亚波长紧凑金属柱阵列薄膜的光透射增强特性,采用3维时域有限差分法进行了模拟,得知该膜的增强光透射谱呈现单主峰带结构,透射谱的峰值位置和带宽也因金属柱阵列周期和金属柱高度的不同而不同,并对金和银两种金属的模型进行了优化计算和分析。结果表明,银柱阵列的峰值归一化透过率最大可达到4.55,通过改变阵列周期可使峰值波长在800nm^1600nm之间变化,其透射带的半峰全宽也由220nm增加到380nm。此研究结果为光带通滤波微器件的设计提供了一种新的方案。

In order to study the enhanced optical transmission characteristics of subwavelength compact metal column arrays film on the glass substrates,3-D finite difference time domain method was adopted to simulate.The enhanced optical transmission spectrum of the film presented a single main peak structure.The peak position and bandwidth of transmission spectrum were different due to the difference of the metal column array period and metal column height.Au and Ag metal model were calculated and analyzed for optimization.The results show that the peak value of the normalized transmittance of Ag column arrays can reach4.55.By altering array period,the peak wavelength changes between 800 nm to 1600 nm.The full width at half maximum of transmission band will increase from 220 nm to 380 nm.The study provides a new solution for the design of micro device about optical band-pass filter.