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arXiv · 1103.6092

Bulk and Surface Magnetization of Co atoms in Rutile Ti_[1-x]Co_xO_[2-delta] Thin Films Revealed by X-Ray Magnetic Circular Dichroism

V. R. Singh·Y. Sakamoto·T. Kataoka·M. Kobayashi·Y. Yamazaki·A. Fujimori·F. -H. Chang·D. -J. Huang·H. -J. Lin·C. T. Chen·H. Toyosaki·T. Fukumura·M. Kawasaki
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Abstract

We have studied magnetism in Ti_[1-x]Co_xO_[2-δ] thin films with various x and δby soft x-ray magnetic circular dichroism (XMCD) measurements at the Co L_[2,3] absorption edges. The estimated ferromagnetic moment by XMCD was 0.15-0.24 μβ/Co in the surface, while in the bulk it was 0.82-2.25 μβ/Co, which is in the same range as the saturation magnetization of 1.0-1.5 μβ/Co. Theseresults suggest that the intrinsic origin of the erromagnetism. The smaller moment of Co atom at surface is an indication of a magnetically dead layer of a few nm thick at the surface of the thin films.

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V. R. Singh, Y. Sakamoto, T. Kataoka, M. Kobayashi, Y. Yamazaki, A. Fujimori, F. -H. Chang, D. -J. Huang, H. -J. Lin, C. T. Chen, H. Toyosaki, T. Fukumura, M. Kawasaki. 2011-04-01. Bulk and Surface Magnetization of Co atoms in Rutile Ti_[1-x]Co_xO_[2-delta] Thin Films Revealed by X-Ray Magnetic Circular Dichroism. https://doi.org/10.1088/0953-8984%2F23%2F17%2F176001

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