中文摘要：

提出一种中心波长随槽型腔腔长线性变化、透射率随耦合距离可调的级联腔表面等离子体滤波器。该滤波器由输入波导、两个级联的介质槽型腔和输出波导组成。通过级联两个相同的槽型腔,共振模被分离从而实现窄带的双通道滤波器;进一步调节输出波导的位置,能够将双通道分离,实现单通道的滤波。通过时域有限差分法和耦合模理论对模型进行仿真分析,结果表明,该滤波器的最小半高宽低至20nm。同基于单槽型腔的滤波器相比,半高宽显著减小。

英文摘要：

A novel and compact narrow band-pass plasmonic filter with tunable wavelength and transmittivity based on cascaded slot cavities is proposed.The structure consists of incident waveguide,two metal-insulator-metal slot cavities and output waveguide.Consequently,a dual-channel filter can be achieved by cascading two identical cavities due to the near-field interaction in metamaterials.By choosing the proper position of the output waveguide,the two channels can be separated from each other without interferences.The structure is numerically investigated by utilizing Finite-Difference Time-Domain（FDTD） simulations and the coupled mode theory（CMT）.Results show that the minimum full-width at half-maximum（FWHM） is about 20 nm,which is obviously narrower than that of the filters based on single slot.