Difunctional terahertz metasurface with switchable polarization conversion and absorption by VO2 and photosensitive silicon

is in the metallic state, the metasurface is switched to be a bidirectional THz absorber for TE and TM wave incidence, and the maximum absorptance of the absorber can reach more than 95%. Furthermore, the absorption is insensitive to the angle of incidence, and the absorption frequency and intensity can be dynamically tuned by changing the polarization angle. By changing the conductivity of the PS, the intensity and frequency of the absorption can also be adjusted. Using the metasurface, we achieved a dynamic multiplexing imaging function for linearly polarized waves. The metasurface showed a new vision for multifunctional THz devices and exhibited a wide application prospect in the field of THz imaging.