Electron mobility variance in metals and degenerate semiconductors

Electron mobility variance in metals and degenerate semiconductors is discussed on the basis of distribution function fluctuation approach. An analytical expression for electron mobility variance is obtained and analyzed. It is established that the mobility variance in Fermi gas depends on average electron concentration, temperature and the electron scattering mechanism. It is revealed that mobility variance dependencies on average electron number and average electron concentration are different: the dependence on average electron number is described by the inverse proportional law but the dependence on average electron concentration is determined by the -5/3 law.