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On the metallic behaviour in dilute two-dimensional systems

A. R. Hamilton·M. Y. Simmons·M. Pepper·D. A. Ritchie
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Abstract

We have studied the metallic behaviour in low density GaAs hole systems, and Si electron systems, close to the apparent two-dimensional metal-insulator transition. Two observations suggest a semi-classical origin for the metallic-like behaviour. Firstly the strength of the metallic behaviour is almost independent of the symmetry of the confining potential, and is predominantly determined by the low temperature resistivity (i.e. by k_F*l). Secondly the fractional decrease in conductivity with increasing temperature depends only on T/T_F, independent of the carrier density, in both systems.

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A. R. Hamilton, M. Y. Simmons, M. Pepper, D. A. Ritchie. 2000-03-17. On the metallic behaviour in dilute two-dimensional systems. https://doi.org/10.1103/physrevlett.87.126802

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