Mapping motion of antiferromagnetic interfacial uncompensated magnetic moment in exchange-biased bilayers
Résumé
In this work, disordered-IrMn3/insulating-Y3Fe5O12 exchange-biased bilayers are studied. The behavior of the net magnetic moment Delta m(AFM) in the antiferromagnet is directly probed by anomalous and planar Hall effects, and anisotropic magnetoresistance. The Delta m(AFM) is proved to come from the interfacial uncompensated magnetic moment. We demonstrate that the exchange bias and rotational hysteresis loss are induced by partial rotation and irreversible switching of the Delta m(AFM). In the athermal training effect, the state of the Delta m(AFM) cannot be recovered after one cycle of hysteresis loop. This work highlights the fundamental role of the Delta m(AFM) in the exchange bias and facilitates the manipulation of antiferromagnetic spintronic devices.