Direct observations of ferromagnetic and antiferromagnetic domains in Pt/Co/Cr<sub>2</sub>O<sub>3</sub>/Pt perpendicular exchange biased film

Yu Shiratsuchi; Yoshinori Kotani; Saori Yoshida; Yasunori Yoshikawa; Kentaro Toyoki; Atsushi Kobane; Ryoichi Nakatani; Tetsuya Nakamura; Yu Shiratsuchi; Yoshinori Kotani; Saori Yoshida; Yasunori Yoshikawa; Kentaro Toyoki; Atsushi Kobane; Ryoichi Nakatani; Tetsuya Nakamura

doi:10.3934/matersci.2015.4.484

AIMS Materials Science

2015, Volume 2, Issue 4: 484-496. doi: 10.3934/matersci.2015.4.484

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Research article Special Issues

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

Received: 27 May 2015 Accepted: 16 November 2015 Published: 19 November 2015

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.
- magnetic domain,
- antiferromagnet,
- exchange bias,
- focused soft X-ray,
- soft X-ray magnetic circular dichroism,
- soft X-ray absorption,
- microspectroscopy,
- fresnel zone plate
Citation: Yu Shiratsuchi, Yoshinori Kotani, Saori Yoshida, Yasunori Yoshikawa, Kentaro Toyoki, Atsushi Kobane, Ryoichi Nakatani, Tetsuya Nakamura. Direct observations of ferromagnetic and antiferromagnetic domains in Pt/Co/Cr2O3/Pt perpendicular exchange biased film[J]. AIMS Materials Science, 2015, 2(4): 484-496. doi: 10.3934/matersci.2015.4.484

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Abstract

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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