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Anomaly of AC resistance in magnetic nanoparticle alloys at spin-glass-like transition

A. B. Pakhomov·J. C. Denardin·M. Knobel·O. F. de Lima
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Abstract

(withdrawn) A combined study of magnetic susceptibility and AC resistance was performed on melt-spun Cu-Co granular magnetic ribbons. The AC resistance as a function of temperature has a sharp maximum. We associate it with a diverging correlation length at the temperature of collective freezing of magnetic moments via increasing magnetic losses in the induced non-uniform field. Application of this model to the experimental data allows a direct determination of the critical exponent of correlation length on both sides of the transition. Giant AC magnetoresistance is observed at the freezing temperature.

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A. B. Pakhomov, J. C. Denardin, M. Knobel, O. F. de Lima. 2000-02-24. Anomaly of AC resistance in magnetic nanoparticle alloys at spin-glass-like transition. https://arxiv.org/abs/cond-mat/9911414

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