title: Giant chiral optical response from a twisted-arc metamaterial.
abstract: We demonstrate enormously strong chiral effects from a photonic metamaterial consisting of an array of dual-layer twisted-arcs with a total thickness of ∼ λ/6. Experimental results reveal a circular dichroism of ∼ 0.35 in the absolute value and a maximum polarization rotation of ∼ 305°/λ in a near-infrared wavelength region. A transmission of greater than 50% is achieved at the frequency where the polarization rotation peaks. Retrieved parameters from measured quantities further indicate an actual optical activity of 76° per λ and a difference of 0.42 in the indices of refraction for the two circularly polarized waves of opposite handedness.
authors.affiliation: School of Materials Science and Engineering, Georgia Institute of Technology , 771 Ferst Drive, Atlanta, Georgia 30332, United States.
authors.forename: Yonghao
authors.initials: Y
authors.lastname: Cui
authors.forename: Lei
authors.initials: L
authors.lastname: Kang
authors.forename: Shoufeng
authors.initials: S
authors.lastname: Lan
authors.forename: Sean
authors.initials: S
authors.lastname: Rodrigues
authors.forename: Wenshan
authors.initials: W
authors.lastname: Cai