Electromagnetic wave scatterings by anisotropic metamaterials: Generalized 4A4 transfer-matrix method

We establish a generalized 4 X 4 transfer- matrix method to study the scatterings of electromagnetic ( EM ) waves by anisotropic metamaterials, with incident waves taking arbitrary polarizations and propagation directions. Employing this method, we illustrate how to manipulate EM wave polarizations freely through reflections by metamaterials. In particular, we show that it is possible to rotate the EM wave polarization direction by an arbitrary angle using a planar metamaterial reflector, in contrast to the conventional Faraday effect requiring a bulk medium. Finite- difference- time- domain simulations on realistic structures are performed to verify all theoretical predictions.