Application of RT-matrixes to the theory of wave reflection from a stratified medium

The reflection and transmission of a wave falling onto a stratified medium is analyzed in terms of the RT-matrixes establishing a relation between the wave amplitudes in the asymptotic regions z→±∞. The RT-matrixes are considered as a generalization of the characteristic matrixes introduced by Abelès with elements expressed via the amplitude reflectance and transmittance of a wave falling onto the medium from the right and left sides. If the medium is divided into several parts, the product of their RT-matrixes is equal to the matrix of the whole medium, whose reflectance and transmittance are thus expressed via the reflectance and transmittance of its parts. The easy use of the RT-matrix in practical calculations was shown through analysis of the wave reflection from periodic and aperiodic multilayer structures with abrupt or smooth interfaces.