Method of surface polariton field structure measurement using resonance excited in a single planar double split ring

An experimental method of determining the structure and local polarization properties of the fields of surface polaritons is proposed, based on excitation of resonance in a single planar double split ring with a diameter much smaller than the wavelength. The proposed method has been verified in the microwave range. A metasurface for the formation of polaritons was represented by a grating of parallel wires with finite lengths. A more than tenfold increase in the resonance intensity has been observed for the excitation of a ring by surface polaritons as compared to the case of excitation by a plane wave.