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arXiv · 0904.4114

On the phase of magneto-oscillations in graphite

L. Smrcka·N. A. Goncharuk
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Abstract

The problem of Dirac fermions in graphite subject to a perpendicular magnetic field is studied. We show analytically that the weak inter-layer interaction between the graphene sheets leads to anomalies in the Shubnikov-de Haas and de Haas-van Alphen magneto-oscillations governed by the orbits around extremal cross-sections of the graphite Fermi surface. The calculation of the Landau plot performed within a four band continuum model reveals that magneto-oscillations are aperiodic, except of the case of vanishing inter-layer interaction at the H point of the graphite Brillouin zone. Also for all other orbits along the H-K-H edge the magneto-oscillations are only asymptotically periodic in the quasi-classical limit, with the phase corresponding to massive fermions.

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L. Smrcka, N. A. Goncharuk. 2009-04-27. On the phase of magneto-oscillations in graphite. https://doi.org/10.1103/physrevb.80.073403

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