Indexed on: 03 Dec '13Published on: 03 Dec '13Published in: Science China Information Sciences
In this paper, we report an analog study of realizing near-field focusing and near-perfect imaging at harmonic frequencies using a two-dimensional (2D) left-handed nonlinear transmission line (LH NLTL) metamaterial. Firstly, we give a detailed procedure of designing LH NLTL and right-handed (RH) transmission line media that match with each other at harmonics. Then, through microwave circuit simulations, we observe strong surface waves at the boundaries between RH and LH NLTL metamaterials, which are consistent with the theoretical analysis of an LH linear superlens. Finally, we show that the LH NLTL metamaterial can act as a flat nonlinear lens that can create, with a subwavelength resolution, an image of harmonic fields of the source which is opaque at the fundamental frequency.