Fully Electrically Driven Liquid Crystal Reconfigurable Intelligent Surface for Terahertz Beam Steering

A rapid response reconfigurable intelligent surface (RIS) based on liquid crystals (LCs) is demonstrated for terahertz beam steering. A wire-controlled metasurface array is achieved by substituting the metal backplane of conventional reconfigurable metasurfaces with pixelated grating electrodes. Notably, the RIS employs bias voltage control across its full states, facilitating accelerated transitions between them. It significantly enhances the response speed of the proposed LC device. Simulation and test results consistently indicate that the RIS exhibits outstanding beam steering capability at the optimal operating frequency of 415 GHz. Specifically, the proposed RIS realizes wide-angle beam scanning from 20° to 60°. Our work is expected to have potential applications in 6G communications, vortex beam generation, and imaging.