Research on surface plasmon band-stop filter based on circular resonant cavities
To investigate the bilateral coupling effect of the bent waveguide structure on the coupling strength,a bent waveguide-coupled circular cavity band-stop filter was proposed with embedded cross silver bars.The filter structure was simulated and analyzed using finite element method.Compared with the existing straight waveguide-coupled circular cavity structure with embedded cross silver bars,the bent waveguide structure has better filtering performance.For instance,the minimum transmittance can be reduced by 10.44%,and the mode 2 blocking-band transmittance can be reduced by nearly 60%when the size of the silver bars is varied.Further studies show that,by adjusting the size and relative angle of the embedded silver bars,the tuning of resonance frequency,the switching between single-band and dual-band,and the control of the half-peak bandwidth can be realized with the minimum half-peak bandwidths of 11.0152 nm and 9.9869 nm,respectively.Moreover,the refractive index sensitivity of the structure remains constant at refractive index of the dielectric from 1 to 1.12.The proposed filter structure has good frequency-selective and narrow-band band-stop filtering characteristics,which is of great application value in narrow-band filtering and WDM systems.
surface plasmon polarizationsmetal-insulator-metal waveguidesbent waveguideband-stop filterscircular cavityfiltering performancefinite element method
国家科技期刊平台
NSTL
万方数据
