Bandpass and bandstop plasmonic filters based on Wilkinson power divider structure

The plasmonic bandpass and bandstop filter based on the Wilkinson power divider structure with the nanoring resonators are proposed and demonstrated. we find that the resonance wavelengths can be manipulated by adjusting the inner radius and outer radius of the nanoring resonator. Using the manipulation of the gap size between the ring resonators and rectangular stubs the bandpass and bandstop filters were designed. When the angle between the input waveguide and ring resonators is changed, the first mode is suppressed. The propagating modes of surface plasmon polaritons (SPPs) are investigated in this filter. The finite-difference time-domain (FDTD) method is utilized to investigate and analyze the transmission characteristics of the proposed filter. The proposed plasmonic filter is of a compact size that has potential application for integrated optics. The proposed technique can suppress the modes. The results show that the filtering wavelength can be manipulated by changing the stubs and rings parameters.