Broadband Magnet Shaped Chiral Metasurface for Asymmetric Transmission of Optical Activity Over Wide Incidence Angle

A novel magnet shaped chiral metasurface is designed for optical activity (rotation of plane of polarization) for K-band applications. The proposed metasurface consists of magnet shaped resonator configured on front and back side of the substrate Roger RT/duroid 5870mm, with thickness of 0.8mm. The structure is analyzed for asymmetric transmission of linearly horizontal and vertical polarized plane waves over wide incidence angles up to 60˚. The proposed design exhibits above 80% efficiency for a broad bandwidth of 3.6GHz, covering the band from 17.6-21.2GHz with asymmetric parameter. The polarization rotation is verified using current distributions on the configured magnet shaped resonators. The material parameters like permittivity, permeability and refractive index are retrieved using effective medium theory.