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arXiv · 0801.1155

Nature of magnetic coupling between Mn ions in as-grown Ga$_{1-x}$Mn$_{x}$As studied by x-ray magnetic circular dichroism

Y. Takeda·M. Kobayashi·T. Okane·T. Ohkochi·J. Okamoto·Y. Saitoh·K. Kobayashi·H. Yamagami·A. Fujimori·A. Tanaka·J. Okabayashi·M. Oshima·S. Ohya·P. N. Hai·M. Tanaka
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Abstract

The magnetic properties of as-grown Ga$_{1-x}$Mn$_{x}$As have been investigated by the systematic measurements of temperature and magnetic field dependent soft x-ray magnetic circular dichroism (XMCD). The {\it intrinsic} XMCD intensity at high temperatures obeys the Curie-Weiss law, but residual spin magnetic moment appears already around 100 K, significantly above Curie temperature ($T_C$), suggesting that short-range ferromagnetic correlations are developed above $T_C$. The present results also suggest that antiferromagnetic interaction between the substitutional and interstitial Mn (Mn$_{int}$) ions exists and that the amount of the Mn$_{int}$ affects $T_C$.

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Y. Takeda, M. Kobayashi, T. Okane, T. Ohkochi, J. Okamoto, Y. Saitoh, K. Kobayashi, H. Yamagami, A. Fujimori, A. Tanaka, J. Okabayashi, M. Oshima, S. Ohya, P. N. Hai, M. Tanaka. 2008-01-09. Nature of magnetic coupling between Mn ions in as-grown Ga$_{1-x}$Mn$_{x}$As studied by x-ray magnetic circular dichroism. https://doi.org/10.1103/physrevlett.100.247202

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