SURFACE-POLARITONS AT THE INTERFACE OF 2 ANISOTROPIC CRYSTALS

The paper presents the results of theoretical and experimental investi gations of phonon polaritons at the free surface of the uniaxial singl e crystal Al2O3- and for the three-layer structure ''vacuum-uniaxial Z nO crystal-uniaxial Al2O3''. The optical axes of the crystals are assu med to be normal to the interfaces of the media. The conditions of the existence of surface polaritons of different types are determined. It is shown that with the help of the attenuated total reflection techni que (ATR) these polaritons could be used for the contactless determina tion of the film thickness as well as for nondamaging control of the m ain parameters of uniaxial crystals.