Intrinsic bistability in the current-voltage characteristics and electroluminescent emission of resonant tunnelling structures

Abstract

Intrinsic bistability in the current-voltage characteristics of double-barrier semiconductor heterostructures arises from the electrostatic effect of the electronic space charge which builds up in the quantum well at resonance. We describe how the effect of a quantising magnetic field greatly enhances this process due to the singularities in the density of electronic states associated with Landau level formation. Appropriately-designed n-type resonant tunneling devices spontaneously emit light (electroluminescence) due to the formation of minority carriers (holes) in impact ionisation processes. The electroluminescence emission can also exhibit a marked intrinsic bistability. We present a microscopic description of the origin of this “optoelectronic memory” effect.