Ultrathin metasurfaces generate multiform beams (electromagnetic, multi-direction, multi-polarization, multi-frequency, and multi-beam) with promising applications in numerous optical traps, modern communication systems, and complex environment identification. However, their capacity to generate required multiform beams concurrently limits their application.
Researchers developed a multifunctional surface with a polarization selection structure and integrated electric and magnetic systems to overcome the primary challenge with the multiform beams. It consists of three weakly coupled layers that can produce various quasi-nondiffracting beams. The top and bottom layers reflect two incident waves, resulting in two quasi-non-diffracting rays. The middle layer, a transmissive surface that can transmit another incident wave, generates the third type of quasi-non-diffracting beams.
The researchers produced and tested the surface for verification. The results of a full-wave simulation and observations show that the proposed surface could generate three quasi-non-diffracting beams.
The measurement results agreed well with the simulation results, demonstrating that the proposed metasurface can effectively generate or receive various beams. The surface designed in this study has potential application prospects in near-field multi-target identification, intelligent communication, and point-to-point data transmission due to advantages such as miniaturization, multifunctional integration, and ease of fabrication. It is worth noting that the method is not limited to microwave frequencies and can be extended to terahertz and optical frequencies.
Related Content: Nanocrystals – Layered Metasurfaces For Infrared Imaging