Electrostatic screening due to non-equilibrium carriers

A simple calculation shows how the electrostatic screening length due to non-equilibrium electrons differs significantly from that for an electron ensemble which is in thermodynamic equilibrium. Its dependence upon the field, the lattice temperature and the effective mass is determined by the prevalent recombination processes, type of trapping center and the dominant scattering mechanisms of the free carriers. The numerical result for high purity Ge at 10 K shows that the screening length for the non-equilibrium electrons at a field of 5.5 v cm(-1) may assume a value less than half of that for the electrons that are in thermodynamic equilibrium. Copyright (C) 1996 Published by Elsevier Science Ltd