A novel miniaturized tri-band metamaterial THz absorber with angular and polarization stability

Abstract

This study presents the design of a novel THz metamaterial absorber with angular stability and polarization insensitivity. The proposed metamaterial absorber is constructed using a square loop enclosing two concentring cross-shaped loops. The proposed unit cell metamaterial has a compact geometry 0.164λeff × 0.164λeff calculated at the lowest operating frequency. The unit cell metamaterial absorber provides dipolar and surface plasmon resonance effect. These resonances provide 98 %, 96 % and 98 % absorption at 0.33 THz, 0.62 THz and 0.82 THz. The parameters of the metamaterial absorber are fully scalable and can be redesigned to suit the needs of any operating frequency by adjusting the lengths of the three loops that compose the unit cell. The symmetric nature of the unit cell absorber provides good polarization stability. The angular stability of the absorber is verified and the results are presented. The proposed metamaterial absorber is a potential choice for use in THz imaging and sensing applications.