基于表面等离子亚波长结构的传输特性,提出一种含金属双缝的金属-电介质-金属波导耦合环形腔结构。由金属双缝波导谐振腔形成的较宽的连续态波与由环形谐振腔形成的较窄的孤立态波耦合干涉相消,形成Fano共振。结合耦合波理论,分析了该结构形成Fano共振的传输及相位特性。采用有限元分析法对该结构进行模拟仿真,定量分析了结构参数对结构慢光特性的影响,实现结构参数优化。结果表明,优化后的结构群折射率可达205。该结构能为集成等离子慢光器件的设计提供有效的理论参考。

Based on the transmission characteristics of surface plasma sub-wavelength structure, a metal-dielectric-metal waveguide coupled ring cavity structure with metallic double-slit is proposed. The Fano resonance is formed by the coupled destructive interference between wide wave with continuous state generated by a metallic double-slit waveguide resonator and narrow wave with isolated state generated by a ring cavity. According to the coupled wave theory, the transmission and phase characteristics of Fano resonance formed by this structure are analyzed. The finite element analysis method is used to simulate the structure, and the effects of the structural parameters on the slow light effect are analyzed quantitatively to optimize the structural parameters. The results show that the optimized group index can reach 205. This structure can provide an effective theoretical reference for the design of integrated plasma slow light devices.