Temperature-dependent high-current breakdown of the quantum Hall effect

We have developed a model of the high-current breakdown of the integer quantum Hall effect, as measured in contactless experiments using a highly-sensitive torsion balance magnetometer. The model predicts that, for low-mobility samples, the critical current for breakdown should decrease linearly with temperature. This prediction is verified experimentally with the addition of a low-temperature ( < similar to 300 mK) saturation of the critical current. It is shown that this saturation is consistent with quasi-elastic inter-Landau-level scattering when the maximum electric field in the sample reaches a large enough value. (C) 2003 Elsevier B.V. All rights reserved