Cluster-layered [Fe/Cr]30 structure exhibited Kondo-like effect studied by GISAXS and Mössbauer spectroscopy

[Display omitted] •Existence of cluster-layered structures in [Fe/Cr]30 was detected by GISAXS.•Synchrotron Mössbauer spectroscopy shows that the thicknesses of the iron clusters do not exceed ∼3–4 atomic monolayers.•Size of the iron clusters has direct impact on Kondo-like behavior and magnetoresistance. Structure and morphology of epitaxial [Fe/Cr]30 multilayers with ultrathin Fe layers (nominally 0.12 nm and 0.08 nm) have been investigated by X-ray reflectivity, synchrotron Mössbauer spectroscopy at low temperature and grazing-incidence small angle X-ray scattering (GISAXS). The films demonstrate Kondo-like behavior of electrical resistivity. The GISAXS patterns reveal their cluster-layered structure. The observed side maxima give the information about the sizes and distances between lateral inhomogeneities. Mössbauer reflectivity spectra measured below the critical angle of the total reflection support the existence of the cluster-layered structure of the samples. Magnetic hyperfine field distributions show that largest number of 57Fe atoms is situated in interfaces of iron clusters and their number increases in the thinnest films.