Barrier breakdown in a multiple quantum well structure

TL;DR

This paper investigates unipolar electronic transport in multiple quantum wells, revealing large current discontinuities caused by impact ionization that switch the structure from resistive to highly conductive states.

Contribution

It demonstrates how impact ionization in quantum wells causes abrupt transitions in electronic transport, a novel insight into quantum well device behavior.

Findings

Current discontinuities up to five orders of magnitude observed.

Impact ionization triggers transition from resistive to conductive state.

Different transport regimes identified via magneto-transport experiments.

Abstract

We explore a regime of unipolar electronic transport in a multiple quantum well structure with very large current discontinuities - up to five orders of magnitude. Magneto-transport experiments reveal different transport regimes. Quantum well impact ionization shifts the structure from a resistive down state, where the current flows through inter-well quantum tunneling, to a highly conductive up state. In the latter regime, the current leaks through a barrier suddenly broken down because of an efficient ionization of the first quantum well.