Influence of ferromagnetic layer on the exchange coupling of antiferromagnetic NiO-based films

Strong effects of ferromagnetic layer (FM-Co, and Ni80Fe20) on the magnitude and blocking temperature of exchange coupling are observed in antiferromagnetic NiO-based films NiO (5nm)/FM1 (t nm)/FM2 (6-t nm). The existence of interfacial spins configuration in glass-like state and FM anisotropy are proposed to interpret a minimum shown in thermal magnetization curves for films with strong exchange coupling effect. The microstructural change of FM layer and the long-range interaction of exchange bias are taken into account to explain a strong dependence of exchange coupling energy density on the thickness t(F) of FM layer when t(F) < 5 nm. (C) 2012 Elsevier B.V. All rights reserved.