Coulomb scattering with remote continuum states in quantum dot devices

TL;DR

This paper presents a theoretical study of Coulomb scattering in quantum dot devices, focusing on remote interactions with continuum states from various sources, and compares results with experimental data.

Contribution

It introduces a comprehensive numerical model for remote Coulomb scattering involving continuum states in quantum dot devices, including microscopic transitions and environmental factors.

Findings

Remote Coulomb scattering depends on electron density, distance, and temperature.

The model aligns with experimental observations of electron lifetime and emission.

Remote scattering significantly influences quantum dot device performance.

Abstract

Electron capture and emission by Coulomb scattering in self-assembled quantum dot (QD) devices is studied theoretically. While the dependence of the Coulomb scattering (Auger) rates on the local wetting layer electron density has been a topic of intense research, we put special interest on the remote scattering between QD electrons and continuum electrons originating from a quantum well, doped bulk layers or metal contacts. Numerical effort is made to include all microscopic transitions between the Fermi distributed continuum states. The remote Coulomb scattering is investigated as a function of the electron density, the distance from the QDs and the temperature. Our results are compared with experimental observations, considering lifetime limitations in QD memory structures as well as the electron emission in pn-diodes.