Magneto-Optical Metamaterials: Nonreciprocal Transmission and Faraday Effect Enhancement

Magneto-optical effects are at the heart of modern technologies providing opportunities for polarization control in laser physics and optical communications, metrology, and in high-density data storage. Here a new type of a hyperbolic magneto-optical metamaterial based on Au-Ni nanorod arrays is developed. The metamaterial exhibits an enhanced magneto-optical response with large rotation of the polarization plane and nonreciprocal light transmission. The effective medium model that incorporates both plasmonic and magneto-optical phenomena in complex multicomponent nanorod media is proposed and validated. The experimental and theoretical results indicate that the magneto-optical response of the nanostructured metamaterial is drastically enhanced and spectrally modified with respect to bulk ferromagnetic media due to interplay between strong anisotropy and magnetic field induced polarization rotation.