Fluctuations in the extrinsic conductivity of disordered conductors

Al'tshuler B. L.

**The fluctuations in the static extrinsic conductivity of disordered metals from one sample to another are discussed. This conductivity of disordered metals is calculated on the basis of the Kubo equation. The mean-square deviation of the total conductivity of a cube from the expectation value of unity in units of ***e*^{2}/fi **is found to be independent of the size of the cube and of its dimensionality. The difference between the observable conductivity and the conductivity found from the Kubo equation is calculated in the region of good metallic conductivity. The situation near the metal-insulator transition is discussed. The effect of spin scattering and of the magnetic field is considered.**