Microscopic model of stacking-fault potential and exciton wave function in GaAs

TL;DR

This paper develops a microscopic model of excitons bound to stacking faults in GaAs, combining structural imaging, density functional, and effective-mass theory, and compares predictions with experimental photoluminescence data.

Contribution

It introduces a detailed microscopic model of stacking-fault excitons in GaAs, linking structural features with excitonic properties and experimental observations.

Findings

Calculated diamagnetic shift matches experimental data.

Provided insights into excitons in double-well potentials.

Model serves as a basis for studying excitonic phases.

Abstract

Two-dimensional stacking fault defects embedded in a bulk crystal can provide a homogeneous trapping potential for carriers and excitons. Here we utilize state-of-the-art structural imaging coupled with density functional and effective-mass theory to build a microscopic model of the stacking-fault exciton. The diamagnetic shift and exciton dipole moment at different magnetic fields are calculated and compared with the experimental photoluminescence of excitons bound to a single stacking fault in GaAs. The model is used to further provide insight into the properties of excitons bound to the double-well potential formed by stacking fault pairs. This microscopic exciton model can be used as an input into models which include exciton-exciton interactions to determine the excitonic phases accessible in this system.