Field dependence of the interface energy in AF/AFM bilayers

In the investigations of antiferromagnetic (AF)/ ferromagnetic (FM) bilayer samples, often distinct experimental techniques yield different values for the measured exchange anisotropy field (HE). Using a simple microscopic model for representing the AF/FM interface, which incorporates the effect of interface roughness, we propose that the observed discrepancy may be accounted for by the dependence of the interface energy between the AF and FM layers with the value of the external applied field (H) as recently observed in anisotropic magnetoresistance measurements, lending support to our proposal.