The antiferromagnetic structures of IrMn3 and their influence on exchange-bias
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Date
2013-08-12
Journal Title
Journal ISSN
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Publisher
Nature Publishing Group
Abstract
We have determined the magnetic structures of single-crystal thin-films of IrMn3 for the crystallographic phases of chemically-ordered L12, and for chemically-disordered face-centred-cubic, which is the phase typically chosen for information-storage devices. For the chemically-ordered L12 thin-film, we find the same triangular magnetic structure as reported for the bulk material. We determine the magnetic structure of the chemically-disordered face-centred-cubic alloy for the first time, which differs from theoretical predictions, with magnetic moments tilted away from the crystal diagonals towards the face-planes. We study the influence of these two antiferromagnetic structures on the exchange-bias properties of an epitaxial body-centred-cubic Fe layer showing that magnetization reversal mechanism and bias-field in the ferromagnetic layer is altered significantly. We report a change of reversal mechanism from in-plane nucleation of 90° domain-walls when coupled to the newly reported cubic structure towards a rotational process, including an out-of-plane magnetization component when coupled to the L12 triangular structure. © 2013, Nature Publishing Group.
Description
Keywords
Anisotropy, Magnetic properties, Microscopy, Electron microscopy, Materials, Diffraction
Citation
Kohn, A., Kovács, A., Fan, R., McIntyre, G. J., Ward, R. C. C., & Goff, J. P. (2013). The antiferromagnetic structures of IrMn3 and their influence on exchange-bias. Scientific Reports, 3, 2412. doi:10.1038/srep02412