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Quantum Hall ferromagnets, cooperative transport anisotropy, and the random field Ising model

J. T. Chalker·D. G. Polyakov·F. Evers·A. D. Mirlin·P. Woelfle
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Abstract

We discuss the behaviour of a quantum Hall system when two Landau levels with opposite spin and combined filling factor near unity are brought into energetic coincidence using an in-plane component of magnetic field. We focus on the interpretation of recent experiments under these conditions [Zeitler et al, Phys. Rev. Lett. 86, 866 (2001); Pan et al, Phys. Rev. B 64, 121305 (2001)], in which a large resistance anisotropy develops at low temperatures. Modelling the systems involved as Ising quantum Hall ferromagnets, we suggest that this transport anisotropy reflects domain formation induced by a random field arising from isotropic sample surface roughness.

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J. T. Chalker, D. G. Polyakov, F. Evers, A. D. Mirlin, P. Woelfle. 2002-08-01. Quantum Hall ferromagnets, cooperative transport anisotropy, and the random field Ising model. https://doi.org/10.1103/physrevb.66.161317

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