Magnetoinductive polaritons: Hybrid modes of metamaterials with interelement coupling

A theory is presented combining effective-medium theory with that of magnetoinductive (MI) waves propagating by virtue of coupling between the resonant elements. The resulting circuit equations for the split-ring resonator (SRR) loaded transmission line are shown to be analogous to those describing a continuous anisotropic magnetic plasma exhibiting spatial dispersion due to interelement coupling. Interelement coupling is also shown to govern the properties of both bulk and surface magnetoinductive polaritons (hybrid polaritonic modes of electromagnetic waves and of slow waves of coupling between resonators). Implications of our method in the design of structures with controllable effective material parameters and with required functionality are demonstrated. We are able to design SRR-based near field manipulating devices for transverse electric (TE) polarization, including a realization of Pendry's near-perfect lens. Considering that surface waves of various kinds have found a wide range of applications in the past, it is envisaged that surface magnetoinductive polaritons will open up fresh possibilities.