Field decomposition and factorization of the Helmholtz determinant operator for bianisotropic media

The paper generalizes the class of media for which the electromagnetic (EM) fields can be decomposed in two independent components. Each of the two components see the medium as a simpler, so called, equivalent medium. This generalization was possible because it was realized that the plane-wave fields satisfy E·D-H·B=0. This discovery allows us to come to a consistent structure for the class of decomposable and factorizable bianisotropic media encompassing all previously studied media as special cases. The class of media of the present paper is shown to be closed with respect to duality transformations. We dare to say that the present paper puts the crown on a long quest for always more general classes of media that allow decomposition and factorization. The equivalent media yield a new class of media that allow a closed form representation of the Green dyadics