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Metal-Insulator Transition in a Low-Mobility Two-Dimensional Electron System

Dragana Popovic·A. B. Fowler·S. Washburn
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Abstract

We have varied the disorder in a two-dimensional electron system in silicon by applying substrate bias. When the disorder becomes sufficiently low, we observe the emergence of the metallic phase, and find evidence for a metal-insulator transition (MIT): the single-parameter scaling of conductivity with temperature near a critical electron density. We obtain the scaling function $β$, which determines the length (or temperature) dependence of the conductance. $β$ is smooth and monotonic, and linear in the logarithm of the conductance near the MIT, in agreement with the scaling theory for interacting systems.

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Dragana Popovic, A. B. Fowler, S. Washburn. 1997-08-21. Metal-Insulator Transition in a Low-Mobility Two-Dimensional Electron System. https://doi.org/10.1016/s0921-4526(98)00295-6

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