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Metal-insulator transition in a 2D electron gas: Equivalence of two approaches for determining the critical point

A. A. Shashkin·S. V. Kravchenko·T. M. Klapwijk
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Abstract

The critical electron density for the metal-insulator transition in a two-dimensional electron gas can be determined by two distinct methods: (i) a sign change of the temperature derivative of the resistance, and (ii) vanishing activation energy and vanishing nonlinearity of current-voltage characteristics as extrapolated from the insulating side. We find that in zero magnetic field (but not in the presence of a parallel magnetic field), both methods give equivalent results, adding support to the existence of a true zero-field metal-insulator transition.

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A. A. Shashkin, S. V. Kravchenko, T. M. Klapwijk. 2001-12-05. Metal-insulator transition in a 2D electron gas: Equivalence of two approaches for determining the critical point. https://doi.org/10.1103/physrevlett.87.266402

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