Numerical simulation research of wide-angle beam steering based on catenary shaped ultrathin metalens

In this paper, a bilayer ultrathin (≈0.153λ) metalens is presented by exploring the advantage of the metasurface with catenary shape and symmetry transformation. The simulation results show that the proposed metalens has high polarization conversion efficiency (>90% even when the incidence angle is 60°), and the wide-angle beam steering ability is beyond ± 70°. Compared with the previous beam steering lens with transmitted array, the metalens in this paper exhibits obvious advantages. Moreover, the longitudinal local catenary fields existing in this metalens can ensure the wide-angle operation for this structure.