Band structure and coupled surface states in one-dimensional photonic crystals

We study a one-dimensional photonic crystal with a complex, frequency-dependent dielectric function. This frequency dependency is either given by the Drude or a Lorentzian dielectric function. In the metallic case an omni-directional metallic bandgap is observed whose size can be controlled by geometric parameters. For the polaritonic photonic crystal one obtains a complete bandgap around the transversal optical plasma frequency. In the last section parallel propagation in such systems is studied: in particular, the surface states in a polaritonic photonic crystal exhibit very interesting features such as negative group velocity.