Radiation enhancement and radiation suppression by a left-handed metamaterial

Abstract

The perfect lens property of a dispersive and lossy left-handed metamaterial (LHM) disk is exploited to superimpose a source of electromagnetic radiation onto its mirror image, formed as a result of reflection from a perfect electric conductor (PEC) or a perfect magnetic conductor (PMC). The superposition of a vertical wire-dipole antenna with its PEC-image results in an increase of the radiation resistance of the antenna compared to that of an antenna emitting in free space. On the other hand, if the same antenna is coupled to a PMC-image it is shown that the result is the formation of a non-radiating configuration. The finite-difference time-domain (FDTD) analysis is performed and this allows a detailed characterization of the systems. It is shown that the non-radiating system allows relatively large amounts of electromagnetic energy to be stored in the LHM-disk and that is indicative of strong electromagnetic fields inside the material. This property is employed in a second-harmonic generation (SHG) process and the potential of a non-radiating configuration as an efficient nonlinear device is demonstrated.