A real-time tunable terahertz metamaterial based on broadside-coupled split ring resonators

This paper reports a real-time tunable metamaterial based on broadside-coupled split ring resonators (BC-SRRs). The device is composed of two layers of SRRs stacked together with an air gap spacer, forming the BC-SRR configuration. One of the layers is fixed, while the other can be driven by an electrostatic comb-drive actuator. The lateral displacement between the two layers of SRRs can be changed by the actuator, resulting in the tuning of the resonance frequencies of the BC-SRRs and the transmission spectrum of the device. The preliminary results show that the resonance frequency can be tuned up to 100GHz corresponding to an 18μm lateral displacement. Our tunable metamaterials have promising applications as THz modulators, filters and sensors.