Continuum model of the twisted graphene bilayer

• Type: Article in International Scientific Journal
• Date: 2012

Authors

Lopes dos Santos, JMBL (Author) FCUP; Peres, NMR (Author) Other; Castro Neto, AH (Author) Other

Journal

Title: Physical Review B - Condensed Matter and Materials Physics

Vol. 86

ISSN: 1098-0121

Publisher: American Physical Society

Indexing

ISI Web of Knowledge - 375 Citations

Scopus - 414 Citations

Scientific classification

FOS: Natural sciences > Physical sciences

Other information

Authenticus ID: P-002-4C2

DOI: 10.1103/physrevb.86.155449

Abstract (EN): The continuum model of the twisted graphene bilayer [Lopes dos Santos, Peres, and Castro Neto, Phys. Rev. Lett. 99, 256802 (2007)] is extended to include all types of commensurate structures. The essential ingredient of the model, the Fourier components of the spatially modulated hopping amplitudes, can be calculated analytically for any type of commensurate structures in the low-twist-angle limit. We show that the Fourier components that could give rise to a gap in the sublattice exchange symmetric (SE-even) structures discussed by Mele [Phys. Rev. B 81, 161405 (2010)] vanish linearly with angle, whereas the amplitudes that saturate to finite values, as theta -> 0, ensure that all low-angle structures share essentially the same physics. We extend our previous calculations beyond the validity of perturbation theory to discuss the disappearance of Dirac cone structure at angles below theta less than or similar to 1 degrees.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 12