Exchange bias in ferromagnetic nanoparticles on antiferromagnetic films

Magnetic properties were investigated for single layer films of closely packed FePt nanoparticles fabricated on nonmagnetic Si substrate and antiferromagnetic CoO films. Temperature dependence of magnetization study showed the enhancement of blocking temperature only for the case of the sample having the interface between ferromagnetic and antiferromagnetic materials. This result suggests that the exchange bias enhanced the anisotropy of nanoparticles.