Chiral characteristics of metasurface based on gammadion cross in THz frequency range

The chiral properties of a metasurface made of 2-D array of twisted gammadion crosses was studied at frequencies ranging from 0.1-0.12 THz. The influences of unit cell design on the optical activity and the ellipticity of the metasurface were revealed. The maximal values of ellipticity and polarization azimuth rotation angle were obtained for the gammadion crosses with petals in the form of the truncated circles. The changing of the semi axes’ relation of gammadion cross ellipses allows tuning of the operational frequency and creation of a multiband polarizer.