Abstract
We investigate how the criticality of the quantum Hall plateau transition in disordered graphene differs from those in the ordinary quantum Hall systems, based on the honeycomb lattice with ripples modeled as random hoppings. The criticality of the graphene-specific Landau level is found to change dramatically to an anomalous, almost exact fixed point as soon as we make the random hopping spatially correlated over a few bond lengths. We attribute this to the preserved chiral symmetry and suppressed scattering between and points in the Brillouin zone. The results suggest that a fixed point for random Dirac fermions with chiral symmetry can be realized in freestanding, clean graphene with ripples.
- Received 10 April 2009
DOI:https://doi.org/10.1103/PhysRevLett.103.156804
©2009 American Physical Society
Synopsis
The rules of disorder
Published 12 October 2009
Disorder causes an unexpected quantum phase transition in graphene.
See more in Physics