Metamaterial

Summary

A metamaterial is an artificial composite with structure on a scale much smaller than the wavelength. This structure gives it effective electromagnetic properties that its ingredients do not have. Its effective permittivity and permeability are set by the shape and arrangement of its building blocks, not only by their chemistry. Metamaterials can have a negative refractive index or strongly anisotropic responses. They are the hardware of transformation optics and of proposals for cloaking and super-resolution.