Electron Localization in the Quantum-Hall Regime

Raffaele Resta

doi:10.1103/physrevlett.95.196805

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Electron Localization in the Quantum-Hall Regime

Raffaele Resta

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Abstract

The theory of the insulating state discriminates between insulators and metals by means of a localization tensor, which is finite in insulators and divergent in metals. In absence of time-reversal symmetry, this same tensor acquires an offdiagonal imaginary part, proportional to the dc transverse conductivity, leading to quantization of the latter in two-dimensional systems. I provide evidence that electron localization--in the above sense--is the common cause for both vanishing of the dc longitudinal conductivity and quantization of the transverse one in quantum-Hall fluids.

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Raffaele Resta. 2005-11-10. Electron Localization in the Quantum-Hall Regime. https://doi.org/10.1103/physrevlett.95.196805

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