JMP  Vol.2 No.9 , September 2011
Spin-Flip Scattering at Quantum Hall Transition
ABSTRACT
We formulate a generalized Chalker-Coddington network model that describes the effect of nuclear spins on the two-dimensional electron gas in the quantum Hall regime. We find exact analytical expression for spin-dependent transmission coefficients of a charged particle through a saddle point potential in a perpendicular magnetic field. Spin-flip scattering creates a metallic state in a finite range around the critical energy of quantum Hall transition. As a result we find that the usual insulating phases with Hall conductance σxy=0,1,2 are separated by novel metallic phases.

Cite this paper
nullV. Kagalovsky and A. Chudnovskiy, "Spin-Flip Scattering at Quantum Hall Transition," Journal of Modern Physics, Vol. 2 No. 9, 2011, pp. 970-976. doi: 10.4236/jmp.2011.29117.
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