Leaky-Wave Radiations by Modulating Surface Impedance on Subwavelength   Corrugated Metal Structures
  One-dimensional (1D) subwavelength corrugated metal structures has been described to support spoof surface plasmon polaritons (SPPs). Here we demonstrate that a modulated 1D subwavelength corrugated metal structure can convert spoof SPPs to propagating waves. The structure is fed at the center through a slit with a connected waveguide on the input side. The subwavelength corrugated metal structure on the output surface is regarded as metasurface and modulated periodically to realize the leaky-wave radiation at the broadside. The surface impedance of the corrugated metal structure is modulated by using cosine function and triangle-wave function, respectively, to reach the radiation effect. Full wave simulations and measuremental results are presented to validate the proposed design. 
Ben Geng Cai, Yun Bo Li, Hui Feng Ma, Wei Xiang Jiang, Qiang Cheng,   Tie Jun Cui
physics.optics physics.class-ph