Asymmetric tri-band linear-to-circular polarization converter in transmission mode

摘要

In this article, we propose a metasurface which has function as tri-band linear-tocirculartransparent polarization converter based on combining multiple plasmonresonances and Fabry-Perot-like resonances. The metasurface is composed of threelayers of metallic pattern arrays separated by two-layer dielectric. The proposedmetamaterial can convert incident linearly polarized waves into circularly polarizedwaves in three frequency bands, and the transmission efficiency reaches up to 90%.When x-polarized forward wave is normally incident, the transmitted right-handedcircular polarized spectra with axial ratio less than 3 dB are in the range of 18.7 to21.5 and 46.1 to 50.3 GHz; the left-handed circular polarized spectrum is 28.7 to34.3 GHz. The physical mechanism of the polarization converter is analyzed indetail, and an experiment is carried out to verify the proposed polarizationconverter.