Extreme enhancement of nonreciprocal wave propagation in magneto-optical metamaterials

We investigate the magnetic field induced spectral properties of metamaterials incorporating indium antimonide (InSb), using electromagnetic probes in the low terahertz frequency regime. An effective medium theory has been developed to explore the behavior of InSb interspersed with a simple dielectric in a gratinglike structure with various thicknesses and grating filling factors. The metamaterial grating structure impacts the light-matter interactions and substantially modifies reflectivity. Our numerical results demonstrate how nonreciprocal reflection can be enhanced and controlled in this spectral region through the composition of the magnetic grating. The current need for higher frequency communication technology drives the relevancy of this study for application to directional-dependent terahertz devices.