Shared-aperture terahertz metasurface with switchable channels

Multifunctional and multiplexed terahertz metasurfaces have attracted considerable attention due to their freedom of manipulating terahertz waves in the space domain. In this paper, we proposed a shared-aperture channel switchable terahertz metasurface, which consists of a top elliptical pattern (i.e., vanadium dioxide (VO ₂ ) and gold configuration), an intermediate SiO ₂ layer and a bottom metal plate. Several coding-pattern arrays are designed to achieve multi-function such as beam splitting, beam focusing, beam deflection, vortex beam, and vortex focusing beams based on Pancharatnam-Berry (PB) mechanism combined with shared-aperture. Furthermore, the single and dual channels can be switched when VO ₂ undergoes a reversible dielectric-metal phase transition around 68°C by controlling the ambient temperature. The full-wave simulation results are in good agreement with the computational predictions. This study greatly enriches the design of terahertz metasurface devices and is highly expected for promising practical applications in future terahertz multiplexing systems.