Abstract
We modify some previous transport theories which consider only the nearest-neighbor hopping in granular metals, and compare the modified theory with the experiment of Abeles et al. In particular, we carry out a critical path analysis, and show that, with practical material parameters, the modified theory gives a value of T 0 (x) in better agreement with the experiment, for the temperature-dependent conductivity σ∝exp [-(T 0 (x)/T) n ] with x = metal volume fraction and n = 1/2 . We have also done a resistor network simulation, and shown that the temperature range over which the exponent n = 1/2 is rather wide and compare reasonably with the experiment of Abeles et al.