Active Controllable Broadband Absorber Based on Vanadium Dioxide

In this paper, we proposed an active controllable terahertz absorber with broadband characteristics, which is composed of the classic three-layer structure of perfect metamaterial absorber with the diagonally placed vanadium dioxide pattern on the top layer. The simulation results show that the bandwidth with absorption greater than 90% is 1.73 THz and the bandwidth ratio is 83% in the range of 1.21 THz-2.94 THz. By using thermal control to change the conductivity of VO2, the absorption can be continuously adjusted from 3% to 95%. In addition, it is also proved that the absorber has polarization insensitive and wide-angle absorption characteristics. The absorber has potential applications in terahertz imaging, sensors and stealth.