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arXiv · 0912.5350

Temperature oscillations of magnetization observed in nanofluid ferromagnetic graphite

S. Sergeenkov·N. S. Souza·C. Speglich·V. A. G. Rivera·C. A. Cardoso·H. Pardo·A. W. Mombru·F. M. Araujo-Moreira
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Abstract

We report on unusual magnetic properties observed in the nanofluid room-temperature ferromagnetic graphite (with an average particle size of l=10nm). More precisely, the measured magnetization exhibits a low-temperature anomaly (attributed to manifestation of finite size effects below the quantum temperature) as well as pronounced temperature oscillations above T=50K (attributed to manifestation of the hard-sphere type pair correlations between ferromagnetic particles in the nanofluid).

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S. Sergeenkov, N. S. Souza, C. Speglich, V. A. G. Rivera, C. A. Cardoso, H. Pardo, A. W. Mombru, F. M. Araujo-Moreira. 2009-12-29. Temperature oscillations of magnetization observed in nanofluid ferromagnetic graphite. https://doi.org/10.1088/0953-8984%2F21%2F49%2F495303

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