LOW-TEMPERATURE HOPPING CONDUCTION IN STRONG ELECTRIC FIELDS. NUMERICAL EXPERIMENT ON A COMPUTER.

A report is given of the results of computer modeling of the current-voltage characteristics of a semiconductor with variable-range hopping conditions and in the low-temperature part of the epsilon //3 conduction region. An analysis is made of a model generally employed to describe hopping conduction in amorphous semiconductors: in this model the density of states near the Fermi level is assumed to be constant and the Coulomb interaction of electrons is ignored. A comparison of the calculated results with the experimental data for a-Ge, a-Sb, and a-As shows that in fact the nonohmic behavior of the current-voltage characteristics is much weaker than predicted by calculations and this clearly means that the model with a constant density of states is unsuitable for the description of such substances and that an increase in the density of states away from the Fermi level should be allowed for.