Liquid-crystal-based Electronically Tunable Metamaterial Modulator in Terahertz Band

We propose a metamaterial (MM) modulation device which is based on nematic liquid crystal (NLC) with double microstructure layers in 330-500 GHz frequency range. The proposed device is composed of an X-shaped periodic structure printed on 280 μm thick quartz substrates. Simulated and experimental results with the device are in general agreement within the designed frequency range. The test results divulge that the maximum modulation depth is 94.34% at 383.45 GHz. When voltage applied to the electrode increases from 0 V to 30 V, the maximum transmittance of the entire frequency range varies from 88.76% to 80.47%, and the resonant frequency is shifted from 372.78 GHz to 340.75 GHz. The proposed device provides effective assistance for millimeter wave and terahertz (THz) bands applications.