Evidence for internal field in graphite: A conduction electron spin resonance study

M. S. Sercheli; Y. Kopelevich; R. Ricardo da Silva; J. H. S. Torres; C. Rettori

doi:10.1016/s0038-1098(01)00465-3

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Evidence for internal field in graphite: A conduction electron spin resonance study

M. S. Sercheli·Y. Kopelevich·R. Ricardo da Silva·J. H. S. Torres·C. Rettori

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Abstract

We report conduction electron spin resonance measurements performed on highly oriented pyrolitic graphite samples between 10 K and 300 K using S (f = 4 GHz), X (f = 9.4 GHz), and Q (f = 34.4 GHz) microwave bands for the external dc-magnetic field applied parallel (H || c) and perpendicular (H perp c) to the sample hexagonal c-axis. The results obtained in the H || c geometry are interpreted in terms of the presence of an effective internal ferromagnetic-like field Heff-int(T,H) that increases as the temperature decreases and the applied dc-magnetic field increases. We associate the occurrence of the Heff-int(T,H) with the field-induced metal-insulator transition in graphite and discuss its origin in the light of relevant theoretical models.

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M. S. Sercheli, Y. Kopelevich, R. Ricardo da Silva, J. H. S. Torres, C. Rettori. 2001-06-12. Evidence for internal field in graphite: A conduction electron spin resonance study. https://doi.org/10.1016/s0038-1098(01)00465-3

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