Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The atomistic origin of the athermal training effect in granular
  IrMn/CoFe bilayers   Anti-ferromagnetic materials have the possibility to offer ultra fast, high
data density spintronic devices. A significant challenge is the reliable
detection of the state of the antiferromagnet, which can be achieved using
exchange bias. Here we develop an atomistic spin model of the athermal training
effect, a well known phenomenon in exchange biased systems where the bias is
significantly reduced after the first hysteresis cycle. We find that the
setting process in granular thin films relies on the presence of interfacial
mixing between the ferromagnetic and antiferromagnetic layers. We
systematically investigate the effect of the intermixing and find that the
exchange bias, switching field and coercivity all increase with increased
intermixing. The interfacial spin state is highly frustrated leading to a
systematic decrease in interfacial ordering of the ferromagnet. This metastable
spin structure of initially irreversible spins leads to a large effective
exchange coupling and thus large increase in the switching field. After the
first hysteresis cycle these metastable spins drop into a reversible ground
state that is repeatable for all subsequent hysteresis cycles, demonstrating
that the effect is truly athermal. Our simulations provide new insights into
the role of interface mixing and the importance of metastable spin structures
in exchange biased systems which could help with the design an optimisation of
antiferromagnetic spintronic devices.

9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
18
The categories of this paper are: econ
25
The categories of this paper are: patt-sol
30
The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph
34
The categories of this paper are: chem-ph
22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
2
The categories of this paper are: math
19
The categories of this paper are: eess
28
The categories of this paper are: alg-geom
3
The categories of this paper are: physics
5
The categories of this paper are: gr-qc
26
The categories of this paper are: bayes-an