Angular dependence of the exchange bias obtained from magnetization and ferromagnetic resonance measurements in exchange-coupled bilayers - art. no. 184411

Theoretical calculations of the angular dependence of the exchange bias fie ld in ferromagnetic/antiferromagnetic bilayers were carried out in the fram ework of a model assuming the formation of a planar domain wall at the anti ferromagnetic side of the interface with the reversal of the ferromagnetic orientation. The calculations were performed for various exchange interacti on field strengths and for both cases of ferromagnetic and anti ferromagnet ic coupling, Analytical expression for the angular dependence of the ferrom agnetic resonance field was obtained as well. It was shown that the exchang e bias field variations derived from ferromagnetic resonance and hysteresis loop measurements become very close for strong interactions only. These fi eld shifts, due to the different magnetization processes involved in the co rresponding measurements, are different physical entities and, in general, must give different values.