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Grazing incidence x-ray diffraction and reflectivity measurements were carried out on ultrathin (a few unit cells thick) superconducting heterostructures, based on Ba0.9Nd0.1CuO(sub 2+x) and CaCuO2 individual blocks, using undulator radiation from a third-generation synchroton. This analysis shows that the interfaces between the different constituent blocks are very sharp with roughness less than one unit cell.

Thin films of LaMn[O.sub.3] (LMO) compounds were prepared by pulsed laser deposition and characterized through x-ray diffraction measurements. The study demonstrates that the epitaxial strain does not induce relevant tilting or rotation of the Mn[O.sub.6] octahedra enough to influence the observed Raman spectra, which did not show any sizable shift or broadening of peaks relative to the typical bulk spectra.

An approach to discriminate between epitaxial strain and other factors responsible for the decrease of the metal-insulator transition temperature (T(sub p)) in thin La(sub 0.7)Sr(sub 0.3)MnO(sub 3) films grown by pulsed laser deposition is presented. The effects of the biaxial strain on T(sub p) are estimated by using this approach.