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Direct observations of ferromagnetic and antiferromagnetic domains in Pt/Co/Cr2O3/Pt perpendicular exchange biased film

1 Department of Materials Science and Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 5650871, Japan;
2 Japan Synchrotron Radiation Research Institute (JASRI)/SPring-8, 1-1-1, Kouto, Sayo, Hyogo 6795198, Japan

Special Issues: X-ray microscopy in Materials Sciences

By using focused soft X-rays, magnetic domain imaging based on X-ray magnetic circular dichroism (XMCD) measurements was performed on a Pt/Co/Cr2O3/Pt film that exhibits both perpendicular magnetic anisotropy and perpendicular exchange anisotropy. In the AC-demagnetized state, spatial distributions of the XMCD corresponding to the magnetic domains were clearly observed. In particular, ferromagnetic and antiferromagnetic magnetic domains were separately observed by tuning the photon energy to either the ferromagnetic Co L3 edge or the antiferromagnetic Cr L3 edge. The ferromagnetic domain pattern is similar to the ones previously reported for Co/Pt multilayers, and the ferromagnetic and antiferromagnetic domains are spatially coupled. The magnetization curve measured after cooling the sample, while maintaining the demagnetized state, exhibited positive and negative exchange biases simultaneously, which suggests that the exchange bias is determined on a domain-by-domain basis.
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Copyright Info: © 2015, Yu Shiratsuchi, et al., licensee AIMS Press. This is an open access article distributed under the terms of the Creative Commons Attribution Licese (http://creativecommons.org/licenses/by/4.0)

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