Broadband Asymmetric Transmission of Linear Polarization in a Tri-Layer Metasurface

In this paper, we report a novel tri-layer structure consisting of diamond-shaped metallic strips sandwiched between two sub-wavelength gratings arrays and printed on two dielectric substrates with a broadband asymmetric transmission phenomenon. Due to the Fabry-Pérot-like effect, the cross-polarization conversion can reach a maximum of 0.94 and exceed 0.7 from 10 GHz to 30 GHz exhibiting a broadband characteristic in microwave spectra. Moreover, our structure is compactness both in the propagating direction and in the transverse directions. It is hoped that the proposed simple, easily fabricated metasurface can be used in further polarization conversion devices and nonreciprocal EM devices.