Energy Level Engineering in In_x Ga_(1-x) As/GaAs Quantum Dots Applicable to QD-Lasers by Changing the Stoichiometric Percentage

TL;DR

This study investigates how varying indium content in In_x Ga_(1-x) As/GaAs quantum dots affects their energy levels, strain, and band gap, providing insights for optimizing QD-lasers.

Contribution

It demonstrates the nonlinear dependence of band gap and recombination energy on indium percentage and analyzes strain tensor behavior with indium inclusion.

Findings

Decreasing recombination energy with higher indium content

Strain tensor components increase with more indium

Band gap reduction is nonlinear with indium percentage

Abstract

Band edge and energy levels of truncated pyramidal In_x Ga_(1-x) As/GaAs (001) quantum dots are studied by single-band effective mass approach, and the dependence to stoichiometric percentages is investigated. It is shown that enhancement of indium percentage decreases the band gap and the recombination energy of electrons and holes. Our principal result is that decrease of recombination energy and band gap is nonlinear and the slopes are different band gap and e-h recombination energy. In addition, it is proved that strain tensor is diagonal along z-axis and the absolute value of the components gets larger by more indium inclusion. Our results appear to be in very good consonance with similar studies. Keywords: quantum dot, band structure, strain tensor, indium percentage.