Integer quantum Hall effect in graphite

Abstract

We present Hall effect measurements on highly oriented pyrolytic graphite that indicate the occurrence of the integer quantum-Hall-effect. The evidence is given by the observation of regular plateau-like structures in the field dependence of the transverse conductivity obtained in van der Pauw configuration. Measurements with the Corbino-disk configuration support this result and indicate that the quasi-linear and non-saturating longitudinal magnetoresistance in graphite is governed by the Hall effect in agreement with a recent theoretical model for disordered semiconductors. Recent experimental [1,2,3,4,5,6] and theoretical [7,8,9] work demonstrates the occurrence of correlated phenomena in the electron system of graphite, indicating that the classical view of the physics of its magnetotransport properties is not adequate. Besides, the quantum Hall effect (QHE) [1] as well as evidence for Dirac fermions (massless particles due to the linear dispersion relation) [5] have been reported for bulk samples of highly oriented pyrolytic graphite of high quality. Recently published results obtained on bulk graphite [10,11], a few layers thick graphite [12], and in graphene (single graphite layer) [13,14] have confirmed both observations and showed that in graphene the QHE is anomalous in that the contribution of the Dirac fermions makes the plateaus to occur at half-integer filling factors. Certainly, the understanding of the electronic properties of graphite is necessary for the development of advanced technology of the graphite-related nanomaterials.

Electrostatic Force Microscopy on Oriented Graphite Surfaces: Coexistence of Insulating and Conducting Behaviors

“…12 an explanation for these results was proposed considering that the current paths are non-homogeneously distributed in the sample, in spite of its high quality. In agreement with this model the magnetoresistance at high enough fields appears to be governed by the Hall resistance, 11 providing a possible solution to the long-standing problem of the quasi-linear and non-saturating magnetoresistance in graphite. 13 In addition, recent theoretical work emphasizes the influence of edge states 14 , curved surfaces and pentagonal or heptagonal defects 15 on the electronic states of graphene sheets.…”

“…2 In a recent experimental work a Corbino disk geometry was prepared on the surface of a high quality HOPG sample. 11 Using a voltage configuration where for a homogeneous sample no Hall signal is expected, clear evidence for an integer QHE was obtained. Based on the disordered semiconductor model of Ref.…”

Sample-Size Effects in the Magnetoresistance of Graphite

“…1) produce a quasi linear behaviour with field of the OMR. A similar picture has been discussed to interpret experiments done with a Corbino disk geometry in HOPG [21] and disordered semiconductors [22]. This is the same thing that happens in optics with the reflection of waves between different media with the addition that some Dirac electron existing in graphite are dispersionless as photons.…”

Erratum to: “Effects of topological defects and local curvature on the electronic properties of planar graphene” [Nucl. Phys. B 763 (2007) 293–308]

“…The density of states turns out to be zero at the Fermi points making useless most of the phenomenological expressions for transport properties in Fermi liquids. Among the unexpected properties are the anomalous behavior of the quasiparticles decaying linearly with frequency [4], and the so-called axial anomaly [5,6] that has acquired special relevance in relation with the recently measured anomalous Hall effect in graphene [1,2,7].…”