Chiral Metasurface for Asymmetric Transmission and Polarization Conversion in Nonreciprocal Shielding

This paper presents a compact chiral metasurface with efficient asymmetric transmission and cross-polarization conversion. The design selectively filters the incoming signals based on their propagation direction and polarization, while blocking the corresponding perpendicular polarization. The design achieves a high asymmetric transmission (AT) factor of 0.954 and a polarization conversion efficiency (PCE) of 99.99% over a bandwidth of 13.7% at 3.65 GHz. Furthermore, the unit cell comprises a compact size of 0.17λ<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">₀</inf> × 0.17λ<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">₀</inf> and a thickness of 0.01λ<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">₀</inf>. Simulation results validate the design suitability for next-generation electromagnetic shielding and sensing applications.