Spin-Flip Scattering at Quantum Hall Transition

Victor Kagalovsky, Alexander L. Chudnovskiy

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DOI: 10.4236/jmp.2011.29117                

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 σ_xy=0,1,2 are separated by novel metallic phases.

Keywords

PACS 73.43.Nq, 72.25.Mk, 73.20.Jc

Conflicts of Interest

The authors declare no conflicts of interest.

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