Dynamically tunable multi-resonance and polarization-insensitive electromagnetically induced transparency-like based on vanadium dioxide film

Abstract

A dynamically tunable multi-resonance and polarization-insensitive electromagnetically induced transparency-like (EIT-like) metamaterial is proposed. The EIT-like structure consists of four cut-wire metals and a square metal frame. Two distinct transparency windows resulting from the near field coupling can be observed under x and y polarization directions, respectively. The physical mechanism of the proposed EIT-like metamaterial can be explained by the surface current distributions. The EIT-like effect can be adjusted by tuning the conductivity of vanadium dioxide (VO2). Meanwhile, a low-loss EIT-like metamaterial can be obtained, which can be proved by the effective medium theory. In addition, the EIT-like metamaterial shows polarization-insensitive characteristics for x and y polarized incidence. By varying the conductivity of VO2, the EIT-like windows and slow-light effect can be manipulated dynamically. These features can provide potential applications in terahertz modulators and slow-light terahertz devices.