Anisotropic metamaterials emulated by tapered waveguides: application to optical cloaking.

We demonstrate that metamaterial devices requiring anisotropic dielectric permittivity and magnetic permeability may be emulated by specially designed tapered waveguides. This approach leads to low-loss, broadband performance. Based on this technique, we demonstrate broadband electromagnetic cloaking in the visible frequency range on a scale approximately 100 times larger than the wavelength.