Behavior of the antiferromagnetic layer during training in exchange-biased bilayers within the domain state model

摘要

An analysis of the antiferromagnetic spins is used to study the training effect in exchange bias bilayers. We use an atomistic model for the magnetic interactions within a classical Heisenberg spin Hamiltonian for the investigation of the temperature dependence of the training effect. Various exchange bias bilayers with different kinds of anisotropy are presented. The spins in the antiferromaget are grouped as stable and unstable according to their behavior during the reversal. It is found that their population changes during the training effect. The stable spins result in a magnetization which is shown to be related to the exchange bias field behavior. The behavior of the interface spins is shown to be determined predominantly by the degree of geometric spin frustration at the interface.