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Ferromagnetism in Oriented Graphite Samples

P. Esquinazi·A. Setzer·R. Hoehne·C. Semmelhack·Y. Kopelevich·D. Spemann·T. Butz·B. Kohlstrunk·M. Loesche
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Abstract

We have studied the magnetization of various, well characterized samples of highly oriented pyrolitic graphite (HOPG), Kish graphite and natural graphite to investigate the recently reported ferromagnetic-like signal and its possible relation to ferromagnetic impurities. The magnetization results obtained for HOPG samples for applied fields parallel to the graphene layers - to minimize the diamagnetic background - show no correlation with the magnetic impurity concentration. Our overall results suggest an intrinsic origin for the ferromagnetism found in graphite. We discuss possible origins of the ferromagnetic signal.

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P. Esquinazi, A. Setzer, R. Hoehne, C. Semmelhack, Y. Kopelevich, D. Spemann, T. Butz, B. Kohlstrunk, M. Loesche. 2002-03-07. Ferromagnetism in Oriented Graphite Samples. https://doi.org/10.1103/physrevb.66.024429

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