ABSTRACT
Recent advances in nanotechnology have inspired researchers to
search for artificial materials with any desired optical response. Of
particular interest are materials with negative refraction, which al-
lows for perfect lensing (Pendry, 2000). Negative refraction requires
both negative permittivity and permeability. Such a response can be
achieved by nanostructuring metals and dielectrics at a scale much
smaller than the optical wavelength (Smith et al., 2004). Indeed,
the approach of metamaterials is to create extreme subwavelength
features that have a strong response, and usually this means a
resonance, in the frequency range of interest.
