Scattering of light in photonic crystals.

We report on the results of a new and exact scattering theory, which describes reflection and transmission of light at the surface of an arbitrarily, shaped photonic crystal by "equivalent surface current distributions", (strata).The method is applied for the calculation of the transmission coefficients of an incoming plane wave by a number of slabs with different widths made of a photonic crystal material. These transmission coefficients show a double exponential behaviour as a function of the width. A generic model is presented leading to a qualitative interpretation of this result.