Ferromagnetic- and Superconducting-like Behavior of Graphite

Y. Kopelevich; P. Esquinazi; J. H. S. Torres; S. Moehlecke

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Ferromagnetic- and Superconducting-like Behavior of Graphite

Y. Kopelevich·P. Esquinazi·J. H. S. Torres·S. Moehlecke

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Abstract

We have identified ferromagnetic- and superconducting-like magnetization hysteresis loops in highly oriented pyrolytic graphite samples below and above room temperature. We also found that both behaviors are very sensitive to low-temperature -- as compared to the sample synthesis temperature -- heat treatment. The possible contribution of magnetic impurities and why these do not appear to be the reason for the observed phenomena is discussed.

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Y. Kopelevich, P. Esquinazi, J. H. S. Torres, S. Moehlecke. 1999-12-23. Ferromagnetic- and Superconducting-like Behavior of Graphite. https://arxiv.org/abs/cond-mat/9912413

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