Electromagnetic metamaterials with zero-refractive index for sub-wavelength photonics

Materials scientists can produce sub-wavelength artificial structures (split rings, honeycomb shapes and many more) to interact with electromagnetic waves so that the propagation of waves can be arbitrarily controlled to achieve desired effects. Among the myriad of these 'metamaterials', metal-dielectric periodic multilayers—hyperbolic metamaterials (HMMs)—are of particular interest. In spite of their simple structure, HMMs have the potential for unique optical applications including