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Possible Metal/Insulator Transition at B=0 in Two Dimensions

S. V. Kravchenko·G. V. Kravchenko·J. E. Furneaux·V. M. Pudalov·M. D'Iorio
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Abstract

We have studied the zero magnetic field resistivity of unique high- mobility two-dimensional electron system in silicon. At very low electron density (but higher than some sample-dependent critical value, $n_{cr}\sim 10^{11}$ cm$^{-2}$), CONVENTIONAL WEAK LOCALIZATION IS OVERPOWERED BY A SHARP DROP OF RESISTIVITY BY AN ORDER OF MAGNITUDE with decreasing temperature below 1--2 K. No further evidence for electron localization is seen down to at least 20 mK. For $n_s<N_{cr}$, the sample is insulating. The resistivity is empirically found to SCALE WITH TEMPERATURE BOTH BELOW AND ABOVE $n_{cr}$ WITH A SINGLE PARAMETER which approaches zero at $n_s=n_{cr}$ suggesting a metal/ insulator phase transition.

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S. V. Kravchenko, G. V. Kravchenko, J. E. Furneaux, V. M. Pudalov, M. D'Iorio. 1994-05-26. Possible Metal/Insulator Transition at B=0 in Two Dimensions. https://doi.org/10.1103/physrevb.50.8039

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