Atomistic theory of electronic and optical properties of InAs/InP self-assembled quantum dots on patterned substrates

TL;DR

This paper develops an atomistic model to analyze how the positioning of InAs quantum dots on patterned InP substrates influences their electronic and optical properties, with implications for tunable quantum dot devices.

Contribution

It presents a detailed atomistic theory incorporating strain and electronic interactions to study quantum dots on patterned substrates, advancing understanding of their tunable optical properties.

Findings

Positioning of quantum dots affects their optical spectra.

Strain distribution influences electronic states.

Template-based tuning of quantum dot properties is feasible.

Abstract

We report on a atomistic theory of electronic structure and optical properties of a single InAs quantum dot grown on InP patterned substrate. The spatial positioning of individual dots using InP nano-templates results in a quantum dot embedded in InP pyramid. The strain distribution of a quantum dot in InP pyramid is calculated using the continuum elasticity theory. The electron and valence hole single-particle states are calculated using atomistic effective-bond-orbital model with second nearest-neighbor interactions, coupled to strain via Bir-Pikus Hamiltonian. The optical properties are determined by solving many-exciton Hamiltonian for interacting electron and hole complexes using the configuration-interaction method. The effect of positioning of quantum dots using nanotemplate on their optical spectra is determined by a comparison with dots on unpatterned substrates, and with experimental results. The possibility of tuning the quantum dot properties with varying the nano-template is explored.