Negative-index metamaterial at 780 nm wavelength

We further miniaturize a recently established silver-based negative-index metamaterial design. By comparing transmittance, reflectance, and phase-sensitive time-of-flight experiments with theory, we infer a real part of the refractive index of -0.6 at a 780 nm wavelength-which is visible in the laboratory. (c) 2006 Optical Society of America.