Optical properties of self-organized wurtzite InN/GaN quantum dots: A combined atomistic tight-binding and full configuration interaction calculation

TL;DR

This study combines atomistic tight-binding and full configuration interaction methods to analyze the electronic and optical properties of self-assembled InN/GaN quantum dots, revealing effects of Coulomb interactions and piezoelectric fields.

Contribution

It introduces a comprehensive atomistic approach to model InN/GaN quantum dots, including crystal structure and Coulomb correlations, providing detailed optical spectra predictions.

Findings

Vanishing exciton and biexciton ground state emission predicted for small lens-shaped dots.

Coulomb correlations significantly influence multi-exciton emission spectra.

Piezoelectric fields alter oscillator strengths and Coulomb matrix elements.

Abstract

In this work we investigate the electronic and optical properties of self-assembled InN/GaN quantum dots. The one-particle states of the low-dimensional heterostructures are provided by a tight-binding model that fully includes the wurtzite crystal structure on an atomistic level. Optical dipole and Coulomb matrix elements are calculated from these one-particle wave functions and serve as an input for full configuration interaction calculations. We present multi-exciton emission spectra and discuss in detail how Coulomb correlations and oscillator strengths are changed by the piezoelectric fields present in the structure. Vanishing exciton and biexciton ground state emission for small lens-shaped dots is predicted.