Two-dimensional left-handed metamaterial with a negative refractive index

We present a two-dimensional metamaterial with left-handed properties in a certain frequency range where both effective dielectric permittivity and magnetic permeability is simultaneously negative. A wedge-shaped metamaterial structure is employed for refractive index measurements. At the left-handed frequency range the structure is shown to have negative refractive index. Phase shift between consecutive number of layers of metamaterial structures are measured and a negative refractive index value is calculated from the amount of the phase shift. The structure is shown to have negative phase velocity. The refractive index values obtained from two different and independent methods are in good agreement. © 2006 IOP Publishing Ltd