Tunable THz absorbers based on LC-tuned Yagi-Uda antennas

Abstract

ABSTRACT This study examines the structural configuration of Yagi-Uda micro-antenna arrays, the resonant properties of which are tunable through nematic liquid crystals in the terahertz spectral region. Reorienting liquid crystals by varying the voltage applied to the liquid crystal cell allows for control of the reflectance and absorbance amplitudes within the 7–12 THz operational frequency range. The reflectance and absorbance control ranges are around 50–60% across most of the frequency range, notably reaching approximately 90% at 11.1 THz. The optimal operational voltage ranges for the presented structure were approximately 1.1–1.9 V at the lower frequencies and 1.4–2.5 V at higher frequencies. This research highlights the potential of such metamaterial designs for efficient and adaptable applications in the THz spectrum.