Meta-material

You need to go through the following papers:
1) The Electrodynamics of substances with simultaneously negative values of permittivity and permeability by V.G. Veselago.
2) Magnetism from Conductors and Enhanced Nonlinear Phenomena By Pendry
3) Composite Medium with simulataneously negative permeability and permittivity By D.R.Smith.

There are lots of papers published by D.R. Smith on Metamaterials.