Recently a device invisible to a static magnetic field was described. The device features a cylinder with two concentric layers. While the inner layer consists of a superconducting material that repels magnetic fields, the outer layer is a ferromagnetic material that attracts them. Placed in a magnetic field, the device has no effect on the field lines, showing neither a shadow nor a reflection. So an object inside the device cannot be detected. www.abc.net.au/science/articles/2012/03/23/3461975.htm My question is: how can one make it work for light (EM field)? What are the physics /equations involved?