High transmission of circularly polarized light and circular dichroism with all-dielectric metamaterial

Abstract

The optical chirality of metamaterials gives birth to distinct responses of left circularly polarized (LCP) and right circularly polarized (RCP) light, leading to asymmetric transmission and circular dichroism (CD) of circularly polarized light. In this work, meta-atom structure composed of square and semicircular combinations were designed, which exhibits extreme high ratio of transmission, reflection and CD values in blue light range. In compare to other reported structures, the structure composed of semicircular and square combinations can achieve better asymmetric transmission. At the wavelength of 460 nm, the incident LCP light can be mostly converted to RCP light, and the incident RCP light can be almost completely reflected. Furthermore, the geometric phase can be controlled by designing the orientation angle of the meta-atom, and the metamaterial can function under any linear or circular polarization and achieving the regulation of the light field. The designed metamaterial provides promising insights into the high CD and possible applications in optical integrated devices, such as anomalously refracted, focusing, and holograms, etc.