Improving imaging performance of a metallic superlens using the long-range surface plasmon polariton mode cutoff...

The metallic superlens is based on excitation and amplification of coupled surface plasmon polariton (SPP) modes through a metal slab. However, the narrow and too-high peaks of the SPP resonance modes in the transfer function can jeopardize imaging performance, such that high sidelobes occur in the image of isolated subwavelength patterns. We propose to design a metallic superlens by approaching the cutoff condition of the long-range SPP mode to flatten the transfer function and to improve imaging performance significantly.