Ag layer thickness dependence of magnetic properties in Fe/Ag superlattices

The magnetic properties of [Fe(20 Angstrom)/Ag(t)](20) superlattices with A g film thickness varying from 7 to 20 Angstrom, prepared by molecular beam epitaxy on (0 0 1)MgO substrate, are presented. The epitaxial growth and th e quality of layered structure of the samples were controlled by RHEED and X-ray diffraction techniques. Magnetic hysteresis loops with the magnetic f ield applied parallel and perpendicular to the plane of the films were dete rmined by vibrating sample magnetometer and superconducting quantum interfe rence device (SQUID) magnetometer at 4.2 K. Magnetotransport properties wer e measured by conventional DC four terminal method with the magnetic field applied parallel to the plane of the films at 4.2 K. The analysis of the hy steresis loops indicates an in plane easy magnetization axis and shows a de pendence of the interface anisotropy on the Ag film thickness. (C) 2000 Els evier Science B.V. All rights reserved.