Elongated gold nanostructures in silica for metamaterials: Technology and optical properties

Nanowire composites are considered as a challenge in design and making of left-handed materials. We established several arrangements on silica glass substrate and show transmission measurements on fields of single nanowires. The results can be interpreted in such a way that the incident electromagnetic wave effectively couple to plasmon modes and lead to negative dielectric permittivity in a particular infrared spectrum. These effects depend on the structure, the topological and geometrical properties of the nanowires and their orientation relative to the wave. Transmission measurements with fields of parallel pairs of nanowires on both sides of the isolating show results that can be well interpreted as negative magnetic permeability and negative dielectric permittivity in the infrared spectra. This arrangement of nanowire pairs can act as a so- called left-handed metamaterial with a negative index of refraction in the infrared and visible spectral ranges.