Reconfigurable Dual-Functional Reflective Polarization Converter Based on Liquid Crystal Terahertz Metasurfaces

This communication presents a reconfigurable polarization converter based on the liquid crystal (LC) terahertz (THz) metasurface. The proposed structure shows unique ability in achieving the conversion from linearly polarized (LP) waves to selective cross-polarized waves or circularly polarized (CP) waves within a wide frequency range. Experimental results demonstrate that, within the frequency region of 318.0-375.6 GHz, the metasurface can achieve the conversion from LP waves to cross-polarized waves without external biasing. However, when a saturated biasing voltage of 8 V is applied, the y-LP waves can be converted to right-handed CP (RHCP) reflection waves. Similar phenomenon is observed for x-LP incidence, as the x-LP waves were converted to left-handed CP (LHCP) wave in reflection. Unlike previously reported single-function metasurface polarization converters, the proposed design offers a new approach for achieving wideband reconfigurable multifunctional polarization conversion with a cost-effective solution, opening up possibilities for its application in the field of THz sensing and communication.