First-principles calculations of the magnetoresistance of Fe/V trilayers and multilayers

Abstract

We report ab initio investigations of the transport properties of Fe–V trilayers and multilayers oriented in the (110) and (001) direction. A fully relativistic Green's function method for layered systems and the Kubo–Greenwood formula have been used to determine the resistances for current in-plane (CIP) and perpendicular-to-the-plane (CPP) geometry depending on the thickness of the spacer. Total energy calculations have revealed that interdiffusion reduces the energy, when the alloying is restricted to a two layer zone at the interfaces. From the transport calculations it is found that the influence of interdiffusion on the magnetoresistance depends on the geometry: it leads to a remarkable reduction in the case of CPP geometry, but is almost unchanged if the current flows parallel to the plane of the layers. Furthermore, small multilayers have been investigated to determine the influence of the boundaries, i.e., Fe leads or vacuum, on the giant magnetoresistance.