Influence of losses on the superresolution performances of an impedance-matched negative-index material

Abstract

We discuss by a Poynting vector analysis how the losses of a negative-index material (NIM) affect the resolution performances of a Veselago–Pendry lens, and we analyze those performances in the framework of the Abbe criterion. The limits of both high losses and low losses are explored. We find that the impedance-matched NIM is able to resolve 30% better than the limit imposed by the Abbe criterion even when the imaginary part of the refractive index (the material losses) exceeds the absolute value of the real part of the refractive index. The NIM is described by a lossy Drude model with equal permittivity and permeability. By increasing the damping parameter of the Drude model, we also explore the regime where both permittivity and permeability are positive and point out the conditions under which the metamaterial is still able to superresolve.