Atomic in-plane disorder in Co/Pt superlattices

We have studied 〈111〉 and 〈001〉 oriented Co(3 Å)/Pt(18 Å) superlattices grown by molecular beam epitaxy via X-ray diffraction using synchrotron radiation. The diffraction peak shapes, for the scattering vector Q parallel to the film planes, were found to be characteristically different between these two films. For the 〈111〉 oriented sample, this broadening is characterized by a Lorentzian peak shape with a positional correlation length of the order of 50 Å. The data further indicate that the atomic correlation in the 〈111〉 sample has a long range orientational but only short range positional order. © 1992 Springer-Verlag.