Terahertz broadband independent electrically tuned phase-shifter based on metamaterial with mutual-coupling magnetic resonance

In this paper, a broadband terahertz phase-shifter based on metamaterial is designed by integrating High Electron Mobility Transistor (HEMT) into a well-designed multi-layer structure unit. It can be independent electrically tuned for three-dimensional (3D) beam control. The variation of carrier density in the HEMT results in a transition of the resonant mode in the multilayer resonant structure. The change of mutual-coupling magnetic resonance provide a phase shift of 180°±15° with a 20% bandwidth in 0.35-0.42 THz. This work facilitated the implementation of 3D terahertz beam control.