Fluctuations of the diffusion coefficient in the subdispersive transport over traps

Abstract

Based on the self-consistent cluster approximation of an effective medium for random walk on a lattice of randomly located traps, the issue of the self-averaging of the diffusion coefficient in the subdispersive mode is examined. It is demonstrated that, in this mode, the diffusion coefficient self-averages slowly according to a power law in the case of three-dimensional space, whereas for the one- and two-dimensional cases, it self-averages poorly, with its relative fluctuations decreasing abnormally slowly, according to a logarithmic law.