A theory of metallic conductivity of the two-dimensional electron gas

It is well known that electron–electron interaction in two-dimensional disordered systems leads to logarithmically divergent Altshuler–Aronov corrections to conductivity at low temperatures (Tτ⪡1; τ is the elastic mean-free time). This work is devoted to the fate of such corrections at intermediate temperatures Tτ>1. We show that in this (ballistic) regime the temperature dependence of conductivity is still governed by the same physical processes as the Altshuler–Aronov corrections—electron scattering by Friedel oscillations. However, in this regime the correction is linear in temperature; the value and even the sign of the slope depends on the strength of electron–electron interaction (this sign change may be relevant for the “metal-insulator” transition observed recently).