Active control of terahertz radiation using a metamaterial loaded with a nematic liquid crystal

ABSTRACT

We experimentally demonstrate an effective method of manipulating terahertz radiation using a metamaterial loaded with a liquid crystal. Active control of the terahertz beam was performed by in-plane electrical switching of the nematic liquid crystal in the metamaterial device. By changing the magnitude of the AC bias voltage from 0 to 100 V, a reversible transmittance shift of up to 10% was achieved for an incident beam with horizontal electric field polarisation and 27% for vertical polarisation with frequency at around 0.7 THz. Metamaterials with electrically tunable characteristics have potential applications in transmission, modulation and switching components and devices for controlling the intensity and phase of terahertz radiation.

Graphical Abstract

KEYWORDS:

• Liquid crystal
• metamaterial
• tunable parameters
• terahertz radiation

Acknowledgements

The authors would like to thank K. Garbat of the Military University of Technology for providing the liquid crystal, and Prof. J. Wróbel of the Institute of Physics Polish Academy of Science for preparing the metamaterial samples.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research was supported by the Polish Ministry of Sciences and Higher Education under Grant No. POIG.01.03.01-14-016/08, titled ‘New Photonic Materials and their Advanced Applications’. We also acknowledge financial support from the Foundation for Polish Science.