金属薄膜上亚波长金属狭缝的非共振光增强透射对宽频带光子器件的设计具有重要意义.为增强金属狭缝的光透射,设计了内嵌矩形腔楔形金属狭缝阵列,并用有限元方法研究了该结构的透射特性.结果表明,内嵌矩形腔的楔形金属狭缝阵列比无矩形腔的楔形金属狭缝阵列透射率高.此外,还研究了矩形腔的结构参数和位置对内嵌矩形腔楔形金属狭缝阵列透射特性的影响.这些结果将对设计具有更高透射能力的金属狭缝具有一定的指导意义.
The non-resonantly enhanced optical transmission phenomenon of sub-wavelength metallic slits on a thin film is significant for broadband light harvesting devices. To improve the efficiency of transmission, in this paper, we propose a compound structure of the tapered metallic slit embedded with rectangular cavity, and its optical properties are investigated by the finite element method. The results show that the compound structure leads to a higher transmission than the tapered metallic slit without rectangular cavity. In addition, the effects of the structure parameters and the position of the rectangular cavity on the transmission property are also studied. These results would be helpful for designing metallic slits with high transmission.