  Development of modern spintronic devices requires materials exhibiting
specific magnetic effects. In this paper, we investigate a magnetization
reversal mechanism in a [Co/Pdx]7/CoO/[Co/Pdy]7 thin-film composite where an
antiferromagnet is sandwiched between a hard and a soft ferromagnets with
different coercivities. The antiferromagnet/ferromagnet interfaces give rise to
the exchange bias effect. The application of soft and hard ferromagnetic films
causes exchange-spring-like behavior while the choice of the Co/Pd multilayers
provides large out-of-plane magnetic anisotropy. We observed that the magnitude
and the sign of the exchange bias anisotropy field are related to the
arrangement of the magnetic moments in the antiferromagnetic layer. This
ordering is induced by the spin orientation present in neighboring
ferromagnetic films which is, in turn, dependent on the orientation and
strength of the external magnetic field.
