How Metamaterials Will Boost Wireless Power Transmission - Technology Review: The new idea is relatively simple. Urzhumov and Smith simply suggest placing a superlens between the two coils in an inductive charger. And that's it.
The work they publish today is a detailed theoretical account of the improvements that such a system would produce. They say that such a lens would take the form of a thin, flat slab of metamaterial and that it would increase the efficiency from being inversely proportional to d^6 to inversely proportional to d^3.