Digital‐Coding‐Feeding Metasurfaces for Differently Polarized Wave Emission, Orbit Angular Momentum Generation, and Scattering Manipulation

Abstract

Coding metasurfaces are two‐dimensional digital metamaterials with unique capability of field programming. For example, the electromagnetic (EM) waves can be flexibly and digitally manipulated in spatial and time domains. However, most of previous coding metasurfaces are presented to control the incident EM waves. Herein, digital‐coding‐feeding (DCF) metasurfaces are proposed to manipulate both radiation and scattered fields, which can realize differently polarized wave emissions, orbit angular momentum (OAM) generations, and scattering controls. The DCF metasurfaces are composed of polarization converters and that with rotation angle of π/2, which are used as the “0” and “1” elements. The 1‐bit DCF metasurfaces are designed, simulated, fabricated, and measured to illustrate the characteristics of scattering manipulation, radar cross‐section reduction, linearly and circularly polarized radiations, and OAM generations. The experimental results are in good agreement with the numerical simulations. The DCF metasurfaces will enhance the digital coding metasurfaces for many applications such as stealth technology, wireless communications, and detection radar systems.