Sub‐Terahertz Broadband Polarization‐Reconfigurable Radiation Based on Spoof Surface Plasmon Polaritons

ABSTRACT Manipulating circular‐, elliptical‐, and linear‐ polarization states of radiation and enhancing the matching efficiency between radiators and receivers/detectors, emerges as a cornerstone technology for achieving high‐quality wireless communications and radar detections. However, reconfiguring these polarization states freely in the chip is still an open challenge over the sub‐terahertz (sub‐THz) band. Here, we achieve broadband sub‐THz polarization‐reconfigurable on‐chip radiation based on a spoof surface plasmon polaritons (SSPPs) platform. By modulating the asymmetric near‐field coupling between the SSPP waveguide and scatter arrays, continuous adjustment of the axial ratio is observed numerically from 1 to 40 dB, enabling the flexible switching among all three classes of polarization states. The experiment also demonstrates this powerful dynamic polarization switching functionality. Our work broadens on‐chip dynamic manipulation of sub‐THz and THz waves and may also open an avenue to secure communication, satellite networks, and local data‐center interconnects.