Electronic structure of strained InP/GaInP quantum dots

TL;DR

This paper models the electronic structure of strained InP/GaInP quantum dots, considering strain, piezoelectric effects, and valence band mixing, revealing electron and hole confinement behaviors and polarization properties.

Contribution

It introduces a comprehensive calculation method for the electronic structure of InP/GaInP quantum dots including strain and piezoelectric effects, with detailed analysis of hole confinement and polarization.

Findings

Electrons confined within the entire island

Holes confined to strain-induced pockets

Decoupled hole states with distinct polarization properties

Abstract

We calculate the electronic structure of nm scale InP islands embedded in $Ga_{0.51}In_{0.49}P$. The calculations are done in the envelope approximation and include the effects of strain, piezoelectric polarization, and mixing among 6 valence bands. The electrons are confined within the entire island, while the holes are confined to strain induced pockets. One pocket forms a ring at the bottom of the island near the substrate interface, while the other is above the island in the GaInP. The two sets of hole states are decoupled. Polarization dependent dipole matrix elements are calculated for both types of hole states.