Multifunctional wavefront-controlled metasurface for generating multiform quasi non-diffracting beams

Abstract

Multiform electromagnetic beams (multi-direction, multi-polarization, multi-frequency, and multi-beam) generated by ultrathin metasurfaces show promising prospects in multiple optical traps, modern communication systems, and identification in complex environments. However, their application is limited by their inability to generate desired multiform beams simultaneously. Here, a multifunctional surface using a polarization selection structure and integrated electric and magnetic structures is proposed to solve the above problem. This surface is composed of three layers with weak coupling that can achieve different quasi-nondiffracting beams. The top and bottom layers are reflective surfaces that can reflect two different incident waves to generate two types of quasi-non-diffracting beams. The middle layer is a transmissive surface that can transmit another incident wave to generate the third type of quasi-non-diffracting beams. For verification, the surface was fabricated and tested. The results of a full-wave simulation and measurements revealed that three different forms of quasi-non-diffracting beams could be generated by the proposed surface.

Efficient electromagnetic analysis of multi‐layer and multi‐scale periodic/quasi‐periodic structures

“…In general, the complexity of the electromagnetic environment is mainly reflected in the multiscale characteristics of the computational region and the large frequency bandwidth of the excitation source. In the process of electromagnetic analysis, many target objects have multi-scale periodic/quasi-periodic characteristics, such as multiple-input multiple-output antenna [1,2], metamaterials surface [3,4] etc. Research on electromagnetic simulation algorithms of periodic arrays [5][6][7] with simple structures or small scale has achieved fruitful achievements.…”