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Topological Phases in Graphitic Cones

P. E. Lammert·V. H. Crespi
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Abstract

The electronic structure of graphitic cones exhibits distinctive topological features associated with the apical disclinations. Aharonov-Bohm magnetoconductance oscillations (period Phi_0) are completely absent in rings fabricated from cones with a single pentagonal disclination. Close to the apex, the local density of states changes qualitatively, either developing a cusp which drops to zero at the Fermi energy, or forming a region of nonzero density across the Fermi energy, a local metalization of graphene.

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P. E. Lammert, V. H. Crespi. 2000-11-30. Topological Phases in Graphitic Cones. https://doi.org/10.1103/physrevlett.85.5190

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