基于金属表面等离子体激元的光调制器研究  

Light Modulator Based on Metal Surface Plasmon Polaritons

作　　者：饶蕾[1] 

机构地区：[1]上海电机学院电子信息学院,上海200240

出　　处：《上海电机学院学报》2013年第4期177-182,共6页Journal of Shanghai Dianji University

基　　金：上海电机学院重点学科资助(10XKF01)

摘　　要：采用模式展开法研究了具有周期性空气孔亚波长阵列的"金属-介质-金属"结构对电磁波的透射特性。由于金属表面等离子体激元具有增强透射效应,使得该结构对电磁波有高通滤波的效果。当两层金属间介质的折射率发生变化时,该结构的透射谱中的峰值频率也随之移动。利用该特性,设计了光调制器结构,通过在该结构的上、下层金属加载电压,即可改变中间层介质的折射率,从而对正入射的光波起到调制作用。研究表明,当介质折射率变化0.5%时,该调制器的调制深度达到88%。Transmission of electromagnetic waves through a metal-dielectric-metal sub-wavelength array with periodic air holes is studied using mode expansion methed in this paper. Since metal surface plasmon polaritons can enhance transmission effect, the structure acts as a high-pass filter. When the re- fraction index of the middle dielectric between two metal layers is changed, peaks of the transmission spectrum also shift in the frequency domain. A light modulator is designed based on this characteristic. Applying voltages on the upper and lower metal layers, the refraction index of the dielectric changes, and light at normal inciden can be modulated accordingly. It is found that when the refraction index changes by 0. 5%, a modulation depth of 88% can be realized.

关 键 词：模式展开法 金属表面等离子体激元 调制器 

分 类 号：TN761[电子电信—电路与系统]