Six-channel programmable coding metasurface simultaneously for orthogonal circular and linear polarizations

Abstract

Metasurfaces have intrigued long-standing research interests and developed multitudinous compelling applications owing to their unprecedented capability for manipulating electromagnetic waves, and the emerging programmable coding metasurfaces (PCMs) provide a real-time reconfigurable platform to dynamically implement customized functions. Nevertheless, most existing PCMs can only act on the single polarization state or perform in the limited polarization channel, which immensely restricts their practical application in multitask intelligent metadevices. Herein, an appealing strategy of the PCM is proposed to realize tunable functions in co-polarized reflection channels of orthogonal circularly polarized waves and in co-polarized and cross-polarized reflection channels of orthogonal linearly polarized waves from 9.0 to 10.5 GHz. In the above six channels, the spin-decoupled programmable meta-atom can achieve high-efficiency reflection and 1-bit digital phase modulation by selecting the specific ON/OFF states of two diodes, and the phase coding sequence of the PCM is dynamically regulated by the field-programmable gate array to generate the desired function. A proof-of-concept prototype is constructed to verify the feasibility of our methodology, and numerous simulation and experimental results are in excellent agreement with the theoretical predictions. This inspiring design opens a new avenue for constructing intelligent metasurfaces with higher serviceability and flexibility, and has tremendous application potential in communication, sensing, and other multifunctional smart metadevices.

Recent advances in electromagnetic metamaterials and metasurfaces for polarization manipulation

“…Wu et al [83] proposed a reconfigurable anisotropic digital coding metasurface loaded with electronically controlled PIN diodes that can achieve independent controls of different polarizations in both transmission and reflection spaces at the same time. Most recently, Liu et al [139] proposed a six-channel programmable coding metasurface to realize tunable functions in co-polarized reflection channels of orthogonal circularly polarized waves and in co-polarized and cross-polarized reflection channels of orthogonal linearly polarized waves from 9.0 to 10.5 GHz (see figure 6(b)).…”