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arXiv · 0902.0929

Temperature dependence of antiferromagnetic susceptibility in ferritin

N. J. O. Silva·A. Millan·F. Palacio·E. Kampert·U. Zeitler·H. Rakoto·V. S. Amaral
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Abstract

We show that antiferromagnetic susceptibility in ferritin increases with temperature between 4.2 K and 180 K (i. e. below the Néel temperature) when taken as the derivative of the magnetization at high fields ($30\times10^4$ Oe). This behavior contrasts with the decrease in temperature previously found, where the susceptibility was determined at lower fields ($5\times10^4$ Oe). At high fields (up to $50 \times10^4$ Oe) the temperature dependence of the antiferromagnetic susceptibility in ferritin nanoparticles approaches the normal behavior of bulk antiferromagnets and nanoparticles considering superantiferromagnetism, this latter leading to a better agreement at high field and low temperature. The contrast with the previous results is due to the insufficient field range used ($< 5 \times10^4$ Oe), not enough to saturate the ferritin uncompensated moment.

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N. J. O. Silva, A. Millan, F. Palacio, E. Kampert, U. Zeitler, H. Rakoto, V. S. Amaral. 2009-02-05. Temperature dependence of antiferromagnetic susceptibility in ferritin. https://doi.org/10.1103/physrevb.79.104405

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