Transverse and longitudinal magnetoresistance in graphite intercalated by Co

Graphite intercalation compounds containing transition metal (Co) were successfully synthesized and their electrical properties investigated over a wide temperature range. These properties were found to be strongly dependent on the initial graphite material used. The results of the XRD investigations indicate that the intercalated compounds of graphite with transition metals could be obtained by the reduction of C8K-intercalated compounds by metal chlorides. The behavior of resistivity, Hall coefficient, transversal and longitudinal magnetoresistance for graphite–Co compounds based on different structure forms of pyrolitic graphites have been studied at 77–300 K temperature range in magnetic field of up to 2 T. And the anomalous Hall coefficient and onset of transversal magnetoresistance have been observed in Co–graphite intercalated compounds. This is caused by the formation of ferromagnetic Co layers in the studied compounds. The anisotropy of the transverse magnetoresistance at the inversion of magnetic field direction was observed. This is related with the onset of additional contribution linearly dependent on magnetic field. This contribution arises due to residual magnetization of ferromagnetic cobalt layers.