A tunable metamaterial absorber employing MEMS actuators in THz regime

As Micro-electromechanical Systems (MEMS) fabrication and actuation methods are very suitable to realize the tunability of metamaterials in terahertz regime, a kind of tunable metamaterial absorber based on MEMS techniques is proposed in this paper. Firstly, an improved electric ring resonator (ERR) absorber model is put forward and the geometrical parameters are optimized to improve the absorption characteristics. Then the feasible fabrication method of the movable ERR structure is discussed. By employing MEMS actuators the frequency of absorption peak is tunable. A simulated full width at half maximum (FWHM) absorbance of 4% is achieved and the simulation results demonstrate a peak absorbance greater than 98% at the whole tunable frequency range from 1.08 THz to 1.20THz.