OPTICAL METHODS IN CHARACTERIZATION OF HTSC THIN-FILM SUBSTRATES

Short overview of optical methods which proved to be useful in the cha racterization of HTSC thin film substrates is presented. Preliminary t ests in polariscopic arrangements, interferometric measurements, optic al absorption and emission spectroscopy reveal macroscopic deficiencie s of the crystal. Intentionally introduced impurity ions serve as prob es of a local strength and symmetry of the crystal field. Results of o ptical study of SrLaGaO4 and SrLaAlO4 crystals are presented and discu ssed.