Annealing temperature dependences of magnetization reversal in exchange-biased bilayers

The thermal stability of the hysteretic properties and domain structures of exchange-coupled Co–Fe/Ir–Mn and Ni–Fe/Ir–Mn bilayers was studied. Using the magneto-optical indicator film technique, X-ray diffractometry and VSM, we have revealed that the layers’ crystal structures are more regular, and also play the main role in the bilayer remagnetization process after annealing procedures. It was found that post-annealing crystal structure leads to changes in the magnetization reversal process. This effect is greater in the Ni–Fe bilayer than in the Co–Fe bilayer.