Eight-band calculations of strained InAs/GaAs quantum dots compared with one, four, and six-band approximations

TL;DR

This paper uses an eight-band strain-dependent k·p model to analyze the electronic structure of pyramidal InAs/GaAs quantum dots, comparing it with simpler band models to evaluate accuracy and effects of strain.

Contribution

It introduces an eight-band model for strained quantum dots and systematically compares it with one, four, and six-band approximations to assess differences in electronic structure predictions.

Findings

Eight-band model predicts lower ground state energy.

Eight-band model shows more excited states.

Strain significantly affects band energies and effective mass.

Abstract

The electronic structure of pyramidal shaped InAs/GaAs quantum dots is calculated using an eight-band strain dependent $\bf k\cdot p$ Hamiltonian. The influence of strain on band energies and the conduction-band effective mass are examined. Single particle bound-state energies and exciton binding energies are computed as functions of island size. The eight-band results are compared with those for one, four and six bands, and with results from a one-band approximation in which m(r) is determined by the local value of the strain. The eight-band model predicts a lower ground state energy and a larger number of excited states than the other approximations.