Quantum Hall effect of massless dirac fermions in a vanishing magnetic field.
Phys Rev Lett
; 100(24): 246806, 2008 Jun 20.
Article
in En
| MEDLINE
| ID: mdl-18643612
ABSTRACT
The effect of strong long-range disorder on the quantization of the Hall conductivity sigma{xy} in graphene is studied numerically. It is shown that increasing Landau-level mixing progressively destroys all plateaus in sigma{xy} except the plateaus at sigma{xy}=-/+e{2}/2h (per valley and per spin). The critical state at the Dirac point is robust to strong disorder and belongs to the universality class of the conventional plateau transitions in the integer quantum Hall effect. We propose that the breaking of time-reversal symmetry by ripples in graphene can realize this quantum critical point in a vanishing magnetic field.
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Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Phys Rev Lett
Year:
2008
Type:
Article
Affiliation country:
Japan