Non-diffraction surface wave with controllable deflection angle by using metasurfaces

Abstract

A planar metasurface Bessel lens has been proposed for non-diffraction surface wave deflection, which is composed of a planar flat lens and an asymmetric gradient refractive index lens. According to the desired refractive index distribution of the two lenses, a metasurface, consisting of sub-wavelength metallic square rings of different sizes, is constructed to realize the planar Bessel lens. Through the planar Bessel lens, the cylindrical-like surface wave radiated from a point source is converted to an inclined non-diffraction surface wave. The planar Bessel lens is fabricated, and the measurement results show good agreement with the full-wave simulation results, which would verify the correctness of the proposed theory.