Quenching of quantum Hall effect and the role of undoped planes in multilayered epitaxial graphene

摘要: We propose a mechanism for the quenching of Shubnikov de Haas oscillations and quantum Hall effect observed in epitaxial graphene. Experimental data show that scattering time conduction electron is magnetic field dependent order cyclotron orbit period, i.e. can be much smaller than zero time. Our scenario involves extraordinary graphene n = 0 Landau level uncharged layers produces high density states at Fermi level. find coupling between this conducting doped plane leads to having right magnitude explain experimental data. PACS numbers: 73.63.Bd, 73.43.-f, 81.05.Uw Graphene two dimensional carbon material which takes form planar honeycomb lattice sp 2 bonded atoms. Its character linear dispersion relation implies that, close charge neutrality point, electrons obey an effective massless Dirac equation. The properties graphene, deriving from equation, are fundamentally different those standard