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On the temperature dependence of 2D "metallic" conductivity in Si inversion layers at intermediate temperatures

S. Das Sarma·E. H. Hwang
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Abstract

We show that the recent experimental claim [Pudalov {\it et al}. \prl {\bf 91}, 126403 (2003) ] of observing ``interaction effects in the conductivity of Si inversion layers at intermediate temperatures'' is incorrect and misleading. In particular, the temperature dependent conductivity $σ$, in contrast to the resistivity (which is what is shown in the paper), does not have a linear temperature regime, rendering the extraction of the slope $dσ/dT$ completely arbitrary. We also show that, at least for higher densities, the standard semiclassical transport theory, which includes realistic disorder effects such as scattering by {\it screened} charged impurity and surface roughness, gives essentially quantitative agreement with the experimental data.

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S. Das Sarma, E. H. Hwang. 2003-10-13. On the temperature dependence of 2D "metallic" conductivity in Si inversion layers at intermediate temperatures. https://doi.org/10.1103/physrevlett.93.269703

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