表面等离激元亚波长光波导滤波器研究进展

综述了本研究小组有关单齿、多齿、侧耦合腔、迂回型等结构的表面等离激元波导滤波器的研究进展.在单齿状金属-电介质-金属波导结构的研究基础上,发展出对称和非对称多齿结构以及侧耦合腔型反射式滤波器、低通波长和高通波长滤波器等其他结构.时域有限差法模拟揭示了它们均可具有一定的波长选择特性,对称多齿结构展现一个宽的陡峭禁带,不对称多齿结构却能实现窄带滤波功能.分析和模拟研究均表明谷或峰的中心波长与齿的深度或宽度有关;截止型结构的截止波长则可通过改变结构的相应长度和宽度等参数来选择.这些滤波器结构有可能应用于未来的纳米集成光学回路.

Research progress of surface plasmon polaritons sub-wavelength optical waveguide filters

In this paper, we review recent progress in our researches on nano-plasmonic waveguide filters based on the tooth/teeth-shaped, side coupled shaped and circuitous shaped structures. A novel plasmonic waveguide filter constructed with a metal-dielectric-metal structure engraved single rectangular tooth is firstly introduced. The structure is then extended to symmetric and asymmetric multiple-teeth structures. A subwavelength side-coupled MDM filter, a low-pass wavelength filter and a high-pass wavelength filter are finally reviewed, respectively. The finite-difference-time-domain method simulation results show that these structures are of the characteristic of wavelength filters with symmetric multiple-teeth structures exhibiting wide and sharp bandgaps, while the asymmetrical multiple-teeth structure can achieve selective narrow-band filtering function. Both analytic and simulation results show that the central wavelengths of reflective or selective filters have relationships with the depth and width of a tooth. And the cutoff wavelengths of the cutoff-type structures can be easily chosen by changing the lengths or the widths of the structures. These filters may have applications to ultrahigh nanoscale integrated photonic circuits.