Circular Dichroism in Dual-Band via Asymmetric Transmissive Chiral Metasurface

Metasurfaces, composed of subwavelength-scale meta-atoms, offer extensive capabilities in electromagnetic (EM) wave manipulation. In this study, we present a dual-functional transmissive chiral metasurface (TCMS) designed to achieve dual-band circular dichroism (CD) at 12.62 GHz and 16.305 GHz within the Ku-band, with CD values of 0.5 and 0.4, respectively, alongside asymmetric transmission (AT). These functionalities are realized simultaneously for right-hand circularly polarized (RHCP) and left-hand circularly polarized (LHCP) incident waves. Simulation results show that the dual-band CD effect is driven by the structural asymmetry of the chiral metasurface. Compared to single-function metasurfaces, this TCMS offers enhanced performance and dual-functionality while maintaining compactness. We believe that this dual-band, dual-functional TCMS, with its simplified geometry, holds significant promise for applications in analytical chemistry, imaging, sensing, spectroscopy, satellite communication, and the development of advanced communication components that enable efficient polarization manipulation.