Dynamic Reflection Phase Modulation in Terahertz Metamaterial

Abstract

In order to provide the terahertz metamaterial with dynamic phase modulation capability, a new strategy is proposed. It consists of two different unit cells involving particularly designed metallic concentric circular split ring resonators, both of which can be controlled with integrated pneumatic actuator and the resultant reflection phase modulation over 320° can be achieved. Based on this concept, a phase gradient metamaterial is designed and dynamic manipulation of the anomalous reflection from 12.3° to -12.5° for normal incidence has been successfully obtained. Moreover, a reflective metalens with 3.15 mm diameter based on current phase tunable metamaterial is also proposed and the dynamic focal length tuning from 0.91 to 2.32 mm has also been demonstrated.