Experimental observation of left-handed transmission in a bilayer metamaterial under normal-to-plane propagation.

We demonstrate experimentally the double-negative (epsilon < 0, micro < 0) transmission band of a one-dimensional metamaterial structure under normal-to-plane propagation in the microwave regime. The structure consists of stacked bilayers of metal cutwire and wire pairs, which are separated by a thin dielectric layer. The existence of the negative index of refraction is inferred from the transmission and phase spectra obtained by using multilayer metamaterial samples. Another metamaterial structure incorporating non-magnetic (electrically shorted) cutwire pairs does not exhibit the corresponding transmission band, which supports the true left-handed behavior of the metamaterial.