Bipartite dielectric Huygens’ metasurface for anomalous refraction

Abstract

Huygens’ metasurfaces—fundamentally based on Schelkunoff's equivalence principle, Huygens’ metasurfaces consist of a two-dimensional array of Huygens’ sources formed by co-located orthogonal electric and magnetic dipoles. Such metasurfaces provide electric and magnetic responses to an incoming electromagnetic (EM) wave, leading to unidirectional scattering and 2π phase coverage. We herein report a near-reflectionless coarsely discretized dielectric Huygens’ metasurface that performs anomalous refraction, offering a low-loss platform for wave manipulation at high frequencies as compared to their lossy metallic analogue. The coarse discretization dramatically simplifies the design, resulting in a metasurface that is highly efficient, cost-effective and robust. In this paper, the proposed metasurface comprises two meta-atoms per period, and is hence named the bipartite dielectric Huygens’ metasurface. Through full-wave simulations at 28 GHz, we show that the proposed metasurface can reroute an incident EM wave from θ i = 15° to θ t = − 44.5° with a very high efficiency: 87% of the scattered power is anomalously transmitted to θ t . Based on our observations, a coarsely discretized dielectric Huygens’ metasurface platform can be efficacious to design meta-devices with multifaceted functionalities in different frequency regimes.