Switchable multi-function device based on reconfiguration metasurface in terahertz region

A terahertz reconfigurable metasurface with multifunction based on vanadium dioxide (VO2) is proposed, which can realize dynamic switching of reflection beam splitting, reflection focusing, vortex beam control and narrowband absorption functions. The designed structure is composed of VO2-aluminum hybrid pattern, polyimide dielectric layer and metal plate. Making use of the phase-changed material, programmable terahertz metasurface with active, switchable controls can be used to realize the flexible functionalities. Depending on predesigned arrangements, the reflected terahertz waves perform diverse states of deflection beams, vortex beams and focused beams, whose angles can be modulated. In addition, the designed structure realizes a high absorption rate over 99.5% at the frequency of 1.69 THz. The proposed metasurface is verified by simulation results for its functionality and feasibility, which has potential application characteristics for terahertz imaging, terahertz communication and sensing.