Tunable terahertz metamaterial using electrostatically electric split-ring resonator

A design of electrostatically tunable metamaterial is proposed in the terahertz (THz) frequency range using electric split-ring resonators (eSRR), which shows polarization-dependent and switching characteristics. The eSRR is composed of anchored rectangular split-ring resonators and a movable middle I-shaped metal bar. By exploiting electrostatic force to change the gap within eSRR and the distance of middle I-shaped metal bar, the electromagnetic characteristics of eSRR can be controlled. The electromagnetic response of eSRR shows a single resonance in transverse electric (TE) mode and keeps as quite stable. In transverse magnetic (TM) mode, the electromagnetic response of eSRR shows dual- and triple-resonance. Such eSRR design is able to be used in lots of applications, such as polarizers, actively tunable filters, frequency-selective detectors, tunable high-efficiency sensors, and multi-functional switches in the THz optoelectronic devices.