从实验和理论两方面来研究了亚波长样品中周期变化时对透过曲线的影响.首先,利用聚焦离子束刻蚀方法和电子束直写系统制备了实验样品:正方和六角晶格空气孔及H-形空气槽.然后,研究了正方和六角晶格空气孔在可见光及近红外波段周期性对透过曲线的影响,证明表面等离子体对透过曲线的增强作用.测量了H-形空气槽在近红外波段的透过曲线,通过H-形空气槽的宽度和周期变化时,透过峰的位置和透过率都有明显变化的实验,进一步证明:表面等离子体对透过光增强起决定性的作用.理论模拟都是基于平面波的传输矩阵方法(TMM),实验和理论模拟很好的结合起来.%The samples of subwavelength hole arrays in metallic films are designed in order to verify the important role of periodicity in enhanced transmissionof light, The samples were fabricated by Electron Beam Lithography (EBL), Focused Ion Beam (FIB) and Reactive Ion Etching (RIE) system. The comparison of optical transmission for the square and hexagon hole arrays shows that the SPPs play the important role in enhanced transmission. We further study the transmission through periodic H-shaped arrays in metallic thin films. The position of transmission peak shifts to the short wavelength by about 140 nm when the line width of H-shaped structure is increased from 120 nm to 200 nm. Our experiment and theory confirm again that the SPPs are the dominant element of the enhanced transmission. The simulation by using Transfer Matrix Method (TMM) reproduces quite well the obtained transmission spectrum.
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