STUDY OF THE CATION DISTRIBUTION IN THE SURFACE-LAYER AND BULK OF SUBSTITUTED IRON-GARNET FILMS

A comparative analysis has been carried out of the physical-chemical s tate of the surface and bulk of single-crystal films of the iron garne t Y2.6Sm0.4Fe3.7Ga1.3O12, on substrates consisting of a gadolinium-gal lium garnet single crystal. To carry out this study, we used the metho d of simultaneous gamma-ray, x-ray, and electron Mossbauer spectroscop y, which made it possible to simultaneously extract information from t he surface layers and the bulk of the sample. This method was applied using a precision system for the motion for the Mossbauer source. It i s shown that the parameters of the hyperfine interactions in the surfa ce layer and in the bulk of the film differ, and that these difference s increase towards the surface. This result is explained by the fact t hat the surface layer is formed as the substrate, together with the sy nthesized film, is removed from the flux and, consequently, the temper ature conditions of synthesis of the bulk and of the surface layer are different. (C) 1997 American Institute of Physics.