State of Mott minimal metallic conductivity in a scaling approach to the metal-insulator transition in doped semiconductors

We show that the temperature-independent conductivity on the metallic side of the metal-insulator transition in doped Ge and Si can be associated with the value of Mott minimal metallic conductivity (Formula presented) The numerical coefficient (Formula presented) for (Formula presented) and (Formula presented) is in agreement with the value predicted by Mott (0.04-0.08), while (Formula presented) for (Formula presented) and (Formula presented) The obtained values of (Formula presented) normalize the scaling behavior of the zero-temperature conductivity σ(0), so that the dimensionless conductivity (Formula presented) for different impurity systems merge into a single dependence for (Formula presented) and (Formula presented).