Plasmon-Enhanced Metasurfaces for Controlling Optical Polarization

A method is proposed for controlling optical polarization using metasurfaces formed from arrays of planar chiral-patterned dielectric metamolecules with embedded achiral plasmonic nanostructures. At plasmon resonance, the subwavelength plasmonic nanoinclusions induce enhanced polarization of the surrounding dielectric, which gives rise to rotation of the polarization azimuth in the transmitted field. Full-wave electromagnetic analysis is used to investigate the optical response of various proposed media as a function of the symmetry and spacing of the metamolecules. The analysis shows that the metamolecules can be tailored to control the polarization state of light and produce frequency selective giant rotation of the polarization azimuth exceeding 10⁵ deg/mm in the visible to near-infrared spectrum with relatively low loss. The proposed method opens up opportunities for the development of versatile ultrathin media that can manipulate optical polarization for novel micro-optical applications. (Graph Presented).