Experimental research of the tunable magnetic plasmon polaritons waveguide filter in microwave band

Based on theoretical analysis, this paper studied experimentally the tunable low-pass, band-stop and band-pass filter effects of the MNG-DPS-MNG (μ-negative materials/double positive materials/μ-negative materials) magnetic plasmon polaritons waveguide. The research results show that the MNG-DPS-MNG waveguide without defect possesses the tunable low-pass filter characteristic. The waveguide with defect in the MNG region possesses the band-stop filter characteristic where the defect is equivalent to a sub wavelength cavity. And the waveguide with cavity in the DPS region possesses the band-pass filter characteristic. So the filter characteristics of the magnetic plasmon polaritons waveguide can be tuned by drawing into the resonators and changing the position and parameters of resonators. The experimental results are in good agreement with the simulation results. These properties will have potential application value in the tunable single channel or multi-channel filters.