Abstract
By designing structures smaller than the wavelength, it is possible to endow the structure with an optical
response on demand. Negative index of refraction material can be constructed by combining
components of negative permittivity and negative permeability. Negative refractive index can make a
perfect lens, while a stack of metal and dielectric layers have hyperbolic dispersion, which assures super
resolution. In optical region, negative permeability is achieved by using a magnetic resonance in
artificial structure such as a pair of metallic platelets. With epsilon nearly zero materials, it is possible to
manipulate phase. By designing spatial distribution of permittivity and permeability, light propagation
can be controlled at will. Recent achievement of metasurface is also introduced.
