title: Diffraction-free surface waves by metasurfaces.
abstract: We propose a method to design and realize planar Bessel lens using artificial metasurfaces to produce diffraction-free surface waves. The planar Bessel lens is composed of two sublenses: a half Maxwell fisheye lens which can shape the surface cylindrical waves to surface plane waves, and an inhomogeneous flat lens which can convert the surface plane waves into approximate diffraction-free surface waves in a diamond-shaped focusing area. Through the planar Bessel lens, a point source on the metasurface directly radiates the diffraction-free surface waves. In realization, we construct the inhomogeneous metasurfaces by subwavelength metallic patches printed on a grounded dielectric substrate. Simulation and experimental results have good agreements, which jointly show the formation of the diffraction-free surface waves in the microwave band.
authors.forename: Yun Bo
authors.initials: YB
authors.lastname: Li
authors.forename: Ben Geng
authors.initials: BG
authors.lastname: Cai
authors.forename: Xiang
authors.initials: X
authors.lastname: Wan
authors.forename: Tie Jun
authors.initials: TJ
authors.lastname: Cui