Switchable dual-function metasurfaces with electromagnetic induction transparency-like and absorption

Two terahertz switchable metasurfaces with dual-function are proposed in this paper. Both metasurfaces contain a periodically arranged pattern layer made of silver, which is mounted on the stacking layer of polyimide and phase change material vanadium dioxide (VO2). The simulation results show that the designed metasurfaces can be converted from multi-band absorbers to electromagnetically induced transparency-like (EIT-like) analogs. When VO2 is in conductive state, the above metasurfaces work as dual-band absorber and tri-band absorber respectively, with absorptivities over 90 %; while VO2 is in insulating state, both structures are EIT-like. The physical mechanism of absorption and EIT-like effect is explained by the surface current distribution. In addition, by adjusting the structural parameters, the peak frequency of the absorbers and the window bandwidth of the EIT-like changes. Meanwhile, the dual-function of the metasurfaces can be maintained within a certain range of incidence and polarization angles. These results show that the switchable metasurfaces can achieve potential applications of modulators, optical buffers, and sensors at terahertz frequencies in the infrared light range.