Velocity and current determination for steadily travelling domains in semiconductors. II

Abstract

The velocity and current determination method proposed in Part Iis applied for the WATKINS--GuNN effect.Two cases ate considered: a) the case of quasi-equilibrium between high-and lowrnobility states (instantaneous transitions) and b) the case of non-instantaneous transitions.For the former case the total current Js and the domain velocity u 0 ate determined separately also including field-dependent diffusion coefficients. For the latter case, ah algebraic equation system is derived for Js and u 0 in terms of "domain shape parameters" S i which characterize the domain shape around the neutrality point.The analysis of the resulting velocity expressions shows that the GUNN domains, in contrast to the slowly moving recombination domains, ate insensitive to the domain shape, at least in GaAs.