Disorder driven splitting of the conductance peak at the Dirac point in graphene

@misc{citeulike:3032197, abstract = {The electronic properties of a bricklayer model, which shares the same topology as the hexagonal lattice of graphene, is investigated numerically. We study the influence of random magnetic field disorder in addition to a strong perpendicular magnetic field. We find a disorder driven splitting of the longitudinal conductance peak within the narrow lowest Landau band near the Dirac point. The energy splitting follows a relation which is proportional to the square root of the magnetic field and linear in the disorder strength. We calculate the scale invariant peaks of the two-terminal conductance and obtain the critical exponents as well as the multifractal properties of the chiral and quantum Hall states. We find approximate values nu \approx 2.5 for the QH states, but nu=0.33 +/- 0.1 for the divergence of the correlation length of the chiral state at E=0 in the presence of a strong magnetic field. Within the central n=0 Landau band, the multifractal properties of both the chiral and the split quantum Hall states are the same, showing a parabolic f(\alpha(s)) distribution with \alpha(0)=2.13 +/- 0.02.}, author = {Schweitzer, L. and Markos, P. }, citeulike-article-id = {3032197}, eprint = {0807.3245}, keywords = {dirac, disorder, graphene, landau, magnetic}, month = {Jul}, posted-at = {2008-07-22 10:00:35}, priority = {2}, title = {Disorder driven splitting of the conductance peak at the Dirac point in graphene}, url = {http://arxiv.org/abs/0807.3245}, year = {2008} }

TY - ELEC ID - citeulike:3032197 L3 - citeulike-article-id:3032197 TI - Disorder driven splitting of the conductance peak at the Dirac point in graphene N2 - The electronic properties of a bricklayer model, which shares the same topology as the hexagonal lattice of graphene, is investigated numerically. We study the influence of random magnetic field disorder in addition to a strong perpendicular magnetic field. We find a disorder driven splitting of the longitudinal conductance peak within the narrow lowest Landau band near the Dirac point. The energy splitting follows a relation which is proportional to the square root of the magnetic field and linear in the disorder strength. We calculate the scale invariant peaks of the two-terminal conductance and obtain the critical exponents as well as the multifractal properties of the chiral and quantum Hall states. We find approximate values nu \approx 2.5 for the QH states, but nu=0.33 +/- 0.1 for the divergence of the correlation length of the chiral state at E=0 in the presence of a strong magnetic field. Within the central n=0 Landau band, the multifractal properties of both the chiral and the split quantum Hall states are the same, showing a parabolic f(\alpha(s)) distribution with \alpha(0)=2.13 +/- 0.02. KW - dirac KW - disorder KW - graphene KW - landau KW - magnetic AU - Schweitzer, L AU - Markos, P PY - 2008/Jul/21/ UR - http://arxiv.org/abs/0807.3245 ER -