基于金属-电介质-金属波导结构的等离子体滤波器的数值研究

基于金属-电介质-金属波导结构, 提出了一种含双侧多支节型等离子波导滤波器, 采用有限元法研究了其透射特性. 在该结构的透射谱中观察到了基于电磁诱导透明效应的四个窄带透射峰, 并通过模场分布有效阐释了透射谱线中峰值、谷值的产生的物理机理. 数值研究同时表明当每个支节长度线性增加时, 透射峰中心波长也将线性增加. 这一结果可用于指导可调谐、多通道窄带滤波器的设计.

Numerical study of plasmonic filter based on metal-insulator-metal waveguide

A novel nanometeric plasmonic filter comprised of double-sided eight stub resonators side-coupled with a metal-isolator-metal waveguide is proposed and demonstrated numerically by the finite element method. The numerical results show that the four transmittance peaks in a transmission spectrum range from 400 nm to 2000 nm can be achieved due to the electromagnetically-induced-transparency-like spectral responses between every two adjacent stub resonators with detuned cavity length. Based on the magnetic field distributions from the two dimensional model, the physical origins of transmittance peaks and dips are clarified by phase analysis of Fabry-Perot resonance effect. In addition, the central wavelengths of transmittance peaks can be tuned by adjusting the cavity length of each stub resonator, which means the waveguide filter could be utilized to develop ultracompact and tunable narrowband photonic filters for high integration.