Universal Crossover between Efros-Shklovskii and Mott Variable-Range-Hopping Regimes

A universal scaling function, describing the crossover between the Mott and\nthe Efros-Shklovskii hopping regimes, is derived, using the percolation picture\nof transport in strongly localized systems. This function is agrees very well\nwith experimental data. Quantitative comparison with experiment allows for the\npossible determination of the role played by polarons in the transport.\n