A Dual-Wideband Bi-Layered Chiral Metamaterial to Develop Cross-Polarization Conversion and Asymmetric Transmission Functionalities for the Linearly Polarized Electromagnetic Waves

Abstract A novel modified bi-layered chiral metamaterial (CMM) with dual-wideband cross-polarization conversion and asymmetric transmission (AT) operations is introduced for the transmission of the linearly polarized electromagnetic (EM) waves. To this end, any unit cell of the presented CMM includes a pair of twisted meander-shaped metallic layers arranged on two opposite sides of a thin dielectric slab. The proposed CMM can cover two frequency bands from 8 GHz to 12 GHz and 14 GHz to 15 GHz, which makes it appropriate to be used in X-band and Ku–band applications. The simulated and measured results with acceptable coincidence indicate that the suggested CMM has a significant potential to transform an incident linearly x− (y−) polarized wave into the orthogonal polarization by transmission across the sample along −z (+z) propagation. Parametric studies of the applied structural modifications are investigated to achieve desirable asymmetric transmission. The realized polarization conversion ratio (PCR) has values above 86% at both operating frequency bands. Also, the obtained polarization rotation azimuth angle θ confirms that the plane of the polarization for the transmitted linearly polarized wave rotates relative to the incident one. Furthermore, the procedures of the cross-polarization conversions are investigated by the surface current distributions at two resonant frequencies.