A reconfigurable ladder-shaped THz metamaterial integrated with a microelectromechanical cantilever array

Abstract

We experimentally demonstrate a microelectromechanically reconfigurable ladder-shaped metamaterial (LS-MM) operating in a terahertz (THz) range. Ultrasmall cantilever actuators with a beam length of 14 μm are employed to independently reshape each unit cell of the LS-MM, correspondingly switching the transmission response of THz waves. The microelectromechanically driven LS-MM achieves a tuning contrast of 60.1% in transmittance at 0.78 THz and a 0.9-rad delay in the transmission phase shift at 1.35 THz through the off-to-on reconfiguration. In particular, the cantilever actuator has a high mechanical resonant frequency of 585 kHz owing to its small size. The microelectromechanically driven LS-MM advantageously offers a pathway for applications requiring fast tunable transmission modulations, such as high-resolution THz imaging and wireless communications.