Strain-controlled correlation effects in self-assembled quantum dot stacks

TL;DR

This paper investigates how elastic interactions in quantum dot stacks differ from single defects and explains the abrupt correlation transitions, predicting alignment angles based on material anisotropy.

Contribution

It introduces a model for elastic interactions in quantum dot stacks that accounts for finite volume effects and predicts alignment behaviors.

Findings

Elastic interactions differ significantly from single defect fields.

Finite volume effects sharpen correlation-anticorrelation transitions.

Predicted inclination angles depend on material anisotropy.

Abstract

We show that elastic interactions of an array of self-assembled quantum dots in a parent material matrix are markedly distinct from the elastic field created by a single point defect, and can explain the observed abrupt correlation--anticorrelation transition in semiconductor quantum dot stacks. Finite volume effects of the quantum dots are shown to lead to sharper transitions. Our analysis also predicts the inclination angle under which the alignment in successive quantum dot layers occurs in dependence on the material anisotropy.