Magnetic properties, interlayer exchange coupling and electric transport in Fe/Cr/Fe trilayers

Abstract

Based on the fully relativistic spin-polarized screened Korringa±Kohn± Rostoker method and the Kubo±Greenwood equation as formulated for layered systems the interlayer exchange coupling (IEC) as well as the magnetoresistance (MR) for the current in-plane (CIP) geometry is calculated for Fe/Cr/ Fe trilayer systems. For the IEC not only short periods of 2 monolayers (ML) but also long periods of about 18 ML are found. For large Cr thicknesses the magnetic moments oscillate with a period of 8±9 ML for even numbers of Cr layers and 18 for odd. The calculated CIP MR and corresponding resistivities are in the range of available experimental data. It is found that the peaks in the CIP MR have little in common with the oscillation periods characterizing the IEC.