Terahertz metasurface enabled by barium strontium titanate ferroelectric film

In this paper, a Ba0.5Sr0.5TiO3 (BST) ferroelectric film is prepared and characterized in the terahertz band. Subsequently, based on the prepared BST film, a metasurface is proposed to manipulate electromagnetic waves. The experimental results indicate that the designed BST metasurface can effectively achieve abnormal beam reflection at around 0.750 THz. Furthermore, by taking advantage of the property that the dielectric constant of the BST film can be altered with an external electric field, a programmable metasurface is proposed. By adjusting the dielectric constant of the BST film, the proposed programmable metasurface can achieve a 1-bit phase response within the frequency range of 0.404-0.410 THz. The far-field simulation results demonstrate that the proposed BST programmable metasurface is capable of realizing dynamic beam steering.