Current filamentation in bistable semiconductor systems with two global constraints

The recent advent of integral circuits combining bistable semiconductor structures with a spatially distributed driving gate has opened up new possibilities for development of self-organizing active media with controllable properties which are of potential interest for neural computer technology. In the present paper the theoretical study of instabilities and current filamentation in such systems is advanced. The consideration is based on a generalized model which treats a gate driven bistable system as an extended active medium with two global constraints related to the main and gate circuits, respectively. It is shown that the presence of a spatially distributed controlling subsystem - a driving gate - leads to a new effect of transversal nonlocal coupling between system elements which acts dramatically upon the system behaviour. The results obtained in a general form regardless of the concrete semiconductor structure design are illustrated by the example of a gate-driven pnpn-structure.