Magnetisation reversal of the ferromagnetic layer in IrMn/CoFe bilayer films

Abstract The magnetisation reversal of the ferromagnetic layer in IrMn/CoFe exchange-coupled films has been investigated using Lorentz microscopy and magnetometry. Results are presented for an IrMn 5nm /CoFe 10nm film. Asymmetry of the reversal mechanism around the magnetisation loop, coercivity enhancement and time-dependent reduction of reversal field have been explained by the existence of pinning sites and thermal activation in the antiferromagnetic layer.