A narrow-band subwavelength plasmonic waveguide filter with asymmetrical multiple-teeth-shaped structure.

Characteristics of a multiple-teeth-shaped plasmonic filter are analyzed. As an extension of this structure, an asymmetrical multiple-teeth-shaped structure is proposed and numerically simulated by using the finite difference time domain method with perfectly matched layer absorbing boundary condition. It is found that the asymmetrical structure can realize the function of a narrow-passband filter. The central wavelength of the passband linearly increases with the simultaneous increasing of d(1) and d(2).