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arXiv · 1103.3172

Topologically Protected Zero Modes in Twisted Bilayer Graphene

R. de Gail·M. O. Goerbig·F. Guinea·G. Montambaux·A. H. Castro Neto
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Abstract

We show that the twisted graphene bilayer can reveal unusual topological properties at low energies, as a consequence of a Dirac-point splitting. These features rely on a symmetry analysis of the electron hopping between the two layers of graphene and we derive a simplified effective low-energy Hamiltonian which captures the essential topological properties of twisted bilayer graphene. The corresponding Landau levels peculiarly reveal a degenerate zero-energy mode which cannot be lifted by strong magnetic fields.

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R. de Gail, M. O. Goerbig, F. Guinea, G. Montambaux, A. H. Castro Neto. 2011-07-20. Topologically Protected Zero Modes in Twisted Bilayer Graphene. https://doi.org/10.1103/physrevb.84.045436

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