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Mobility-Dependence of the Critical Density in Two-Dimensional Systems: An Empirical Relation

M. P. Sarachik
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Abstract

For five different electron and hole systems in two dimensions (Si MOSFET's, p-GaAs, p-SiGe, n-GaAs and n-AlAs), the critical density, $n_c$ that marks the onset of strong localization is shown to be a single power-law function of the scattering rate $1/τ$ deduced from the maximum mobility. The resulting curve defines the boundary separating a localized phase from a phase that exhibits metallic behavior. The critical density $n_c \to 0$ in the limit of infinite mobility.

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M. P. Sarachik. 2001-05-31. Mobility-Dependence of the Critical Density in Two-Dimensional Systems: An Empirical Relation. https://doi.org/10.1209/epl%2Fi2002-00496-6

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