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Dirac Fermion Confinement in Graphene

N. M. R. Peres·A. H. Castro Neto·F. Guinea
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Abstract

We study the problem of Dirac fermion confinement in graphene in the presence of a perpendicular magnetic field B. We show, analytically and numerically, that confinement leads to anomalies in the electronic spectrum and to a magnetic field dependent crossover from \sqrt{B}, characteristic of Dirac-Landau level behavior, to linear in B behavior, characteristic of confinement. This crossover occurs when the radius of the Landau level becomes of the order of the width of the system. As a result, we show that the Shubnikov-de Haas oscillations also change as a function of field, and lead to a singular Landau plot. We show that our theory is in excellent agreement with the experimental data.

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N. M. R. Peres, A. H. Castro Neto, F. Guinea. 2006-04-03. Dirac Fermion Confinement in Graphene. https://doi.org/10.1103/physrevb.73.241403

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