Landau level broadening in graphene with long-range disorder -- Robustness of the n=0 level

Tohru Kawarabayashi, Yasuhiro Hatsugai, Hideo Aoki

Published 2009-08-28Version 1

Broadening of the Landau levels in graphene and the associated quantum Hall plateau-to-plateau transition are investigated numerically. For correlated bond disorder, the graphene-specific n=0 Landau level of the Dirac fermions becomes anomalously sharp accompanied by the Hall transition exhibiting a fixed-point-like criticality. Similarly anomalous behavior for the n=0 Landau level is also shown to occur in correlated random magnetic fields, which suggests that the anomaly is generic to disorders that preserve the chiral symmetry.