LAYERED SEMICONDUCTOR GES AS A BIREFRINGENT STRATIFIED MEDIUM

Transmission and reflection spectra of GeS single crystals of differen t thicknesses have been measured in a wide spectral range. The interfe rence spectra have two periods in unpolarized light, one of which is t he usual Fabry-Perot type while the other is due to birefringence. It is also shown that the reflection coefficient in the transparent regio n depends on the crystal thickness and reaches the value of about 0.75 for thick crystals (similar to 800 mu m). The results obtained have b een analyzed by using the 4 x 4 matrix method for multilayer optical s ystems. It is shown that GeS can be considered as a natural birefringe nt stratified medium.