The electric transport properties of a rather complicated spin-valve system containing NiFe permalloy, CoFe hard magnets and two types of spacers (Cu,Ru) are investigated theoretically in terms of the relativistic spin-polarized versions of the Screened Korringa-Kohn-Rostoker method and the Kubo-Greenwood equation. It is found that the regimes of antiferromagnetic coupling relevant for the giant magnetoresistance (GMR) are mostly determined by the thickness of the Cu-spacer: the nodes of oscillation of the interlayer exchange coupling (IEC) with respect to the Cu-spacer thickness are shifted only marginally by the presence of a very thin Ru cap. Also found are oscillations of the IEC and GMR with respect to the thickness of the hard magnet parts of the system (CoFe) and with respect to the Ru-spacer thickness. Viewed with respect to the thickness of the Cu-spacer the minima in and the actual value of the giant magnetoresistance as a function of the thickness of the Ru-spacer are in rather good agreement with experiment.
|Number of pages||7|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - Oct 1 2002|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics