High Efficiency and Wideband Polarization Converter Design in Terahertz Region

In this study, the design of an adaptable, high-efficiency, and broadband polarization converter in the terahetz (THz) region was carried out in a computer environment with the electromagnetic simulation program CST Microwave Studio. Current density at the resonance frequencies of the designed model, reflection coefficients for the polarization converter, polarization conversion ratios, orthogonal components, and phase differences were examined in Excel graphics. The metamaterial designed as substrate Gold (Au), middle layer Rogers RT5880LZ, and top layer vanadium dioxide (VO2)-Au composition, with the Bruggeman effect model, and the dielectric constant of VO2 being taken as ε=9, has a Polarization Conversion Ratio (PCR), of over 90% in the range of 5.29-13.68 THz the relative bandwidth (RBW) was calculated as 88.40%. When the dielectric constant of VO2 is taken as ε=12 with the Drude model, the RBW is calculated as 89.39% with a PCR of over 90% in the range of 5.20-13.61 THz. The designed model is 5.4 μm thick, adaptable, and highly efficient. In addition, a dynamic metamaterial was designed because the conductivity level of VO2 changes according to temperature.