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Classical versus Quantum Transport near Quantum Hall Transitions

Efrat Shimshoni
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Abstract

In attempt to settle the apparent disagreements between different experimental results, transport data near quantum Hall transitions are interpreted by identifying two distinct conduction regimes. The ``classical'' regime, dominated by nearest neighbor hopping between localized conducting puddles, manifests an activated-like resistivity formula, and the quantized Hall insulator behavior. At very low temperatures $T$, or farther from the critical point, a crossover occurs to a "quantum" transport regime dominated by variable range hopping. The latter is characterized by a different T-dependence, yet the dependence on filling fraction is, coincidentally, hard to distinguish.

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Efrat Shimshoni. 1999-04-11. Classical versus Quantum Transport near Quantum Hall Transitions. https://doi.org/10.1103/physrevb.60.10691

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