Current filaments and nonlinear oscillations in n-GaAs

Abstract

Experimental investigations of nonlinear oscillations and the formation of current filaments due to impact ionization of shallow donors in n-GaAs at low temperatures are summarized. Measurements of the temporal and spatial structure of nonequilibrium current flow provided a concise microscopic basis of the observed regular, quasiperiodic, frequency-locked and chaotic current fluctuations.