High-Efficiency Compact Huygens' Metasurface for Orbital Angular Momentum Generation

Huygens' metasurface provides powerful method to designing high-efficiency meta-devices via balancing the electric/magnetic responses at the interface. However, most of the previously reported works operate in the transmission mode, leaving the reflection property to be unexploited. In this paper, a novel miniaturized reflective Huygens' meta-atom and metasurface is proposed. It comprises one vertically placed modified split resonant ring resonator (MSRR) and one planar terminally-bent electric dipole resonator (TBEDR), which provides the required magnetic and electric responses for constructing the Huygens resonance, respectively. Through judiciously adjustment on the key structural parameters, nearly full 2π reflection phase coverage is easily fulfilled together with high reflectance. As proof-of-concept demonstration, a high-efficiency reflective OAM generator is designed and simulated, and a good coincidence is witnessed between the simulation results and the design goals. The proposed work with merits of high-efficiency, compact size can be competitive candidate for the six-generation (6G) wireless communication system.