Magnetic plasmon hybridization and optical activity at optical frequencies in metallic nanostructures

The excitation of optical magnetic plasmons in chiral metallic nanostructures based on a magnetic dimer is studied theoretically. Hybridization of the magnetic plasmon modes and a type of optical activity is demonstrated at near-infrared frequencies. A linearly polarized electromagnetic wave is shown to change its polarization after passing through an array of magnetic dimers. The polarization of the transmitted wave rotates counterclockwise at incident light frequencies corresponding to the low energy and clockwise at the high energy magnetic plasmon state. A metamaterial made of a large number of coupled magnetic dimers could be utilized as a tunable optically active medium with possible applications in optical elements and devices.