摘要
A significant exchange bias （EB） traimng ettect has been observea in sputter deposited FeAu/FeNi bilayers, wherein the exchange field （HE） exhibits a special sign-changeable temperature dependence. Very interestingly, despite the absence of multiple easy axes in the FeAu spin glass （SG） layer, HE drops abruptly between the first and second magnetic cycles, which is followed by a more gradual continuous change in the subsequent cycles. This training behavior cannot be described by the empirical n-1/2 law because of the asymmetric magnetization reversal processes. We propose modifying Binek＇s model to include the asymmetric changes of the pinning SG spins at the descending and ascending branches. This new model successfully describes the EB training effect in FeAu/FeNi bilayers.
A significant exchange bias （EB） traimng ettect has been observea in sputter deposited FeAu/FeNi bilayers, wherein the exchange field （HE） exhibits a special sign-changeable temperature dependence. Very interestingly, despite the absence of multiple easy axes in the FeAu spin glass （SG） layer, HE drops abruptly between the first and second magnetic cycles, which is followed by a more gradual continuous change in the subsequent cycles. This training behavior cannot be described by the empirical n-1/2 law because of the asymmetric magnetization reversal processes. We propose modifying Binek＇s model to include the asymmetric changes of the pinning SG spins at the descending and ascending branches. This new model successfully describes the EB training effect in FeAu/FeNi bilayers.
基金
Project supported by the National Basic Research Program of China(Grant Nos.2014CB921101 and 2010CB923401)
the National Natural Science Foundations of China(Grant Nos.51331004,11074112,and 11174131)
