Tuning characteristics of mirrorlike T-shape terahertz metamaterial using out-of-plane actuated cantilevers

We present a mirrorlike T-shape metamaterial (MTM) with out-of-plane movable microstructures for enabling active tuning of resonant frequency in the terahertz (THz) region. The resonant frequency of MTM device can be actively controlled by using either electrostatic force or liquid force. First, by gradually increasing the bias, the cantilevers were continuously deformed towards the substrate and then completely snapped down when the bias reached the critical pull-in voltage (12 V). The tuning range is 0.50 THz as compared to the device without driving voltage to that operated at the pull-in voltage. Meanwhile, we dropped different liquids on the snap-down device surface. In the case of device covered with deionised water, the resonant frequency shift of 0.17 and 0.21 THz were measured for inductive-capacitive and dipolar resonances, respectively. Furthermore, we also demonstrate the flow tuning capability of MTM device integrated with a polydimethylsiloxane fluidic channel by using different injection flow rate from 0 to 5 ml/min. The tunability of MTM device is 0.30 THz due to the different bending states of the MTM cantilevers under different liquid forces. (C) 2014 AIP Publishing LLC.