Studies on antiferromagnetic/ferromagnetic interfaces

The spin valve with a synthetic pinned layer serves as an excellent system to study the interfacial properties of antiferromagnetic-ferromagnetic film s (AFM/FM). Using this system, we have unambiguously determined that the di rection of the exchange bias is totally determined by the direction of magn etization of the ferromagnetic films and not by the applied magnetic field. The two surfaces of 50 Angstrom antiferromagnetic thin film are able to pr ovide exchange bias at the interfaces of both the upper and lower ferromagn etic films. Furthermore, the exchange bias can be set along any direction f or the polycrystalline AFM/FM films. The exchange coupling of AFM/FM films appears to occur at the AFM/FM interface where the surface spins in the mat ching grains favor exchange interactions. (C) 2000 Published by Elsevier Sc ience B.V. All rights reserved.