Determination of Spectral Focusing Features of a Metamaterial Slab

Abstract: The realization of flat superlenses is a major application area of metamaterials. A slab of double negative (DNG) material is capable of imaging with a resolution beyond the diffraction limit. The focusing quality depends primarily on the amount by which the original wavenumber spectrum of the source is restored behind the lens. Even a small deviation from the ideal case of r = μr =-1 limits the wavenumber spectrum of the transmitted field, which may result in a significant degradation of the focusing quality. In this work we determine the width of the trans-mitted wavenumber spectrum as a function of the configuration parameters and establish a relation between the spectrum width and the imaging quality. Restrictions imposed on the focusing char-acteristics and difficulties arising in full wave simulations will be pointed out