Excitons in coupled InAs/InP self-assembled quantum wires

TL;DR

This study investigates excitonic optical transitions in coupled InAs/InP quantum wires, analyzing energy states, photoluminescence, and coupling regimes with strain effects included, revealing anti-crossings indicative of symmetry changes.

Contribution

It provides a detailed theoretical analysis of excitons in coupled quantum wires, including strain effects and identification of different coupling regimes through energy state behavior.

Findings

Anti-crossing of excited state energies in vertically coupled wires

Determined quantum wire heights from photoluminescence comparison

Identified symmetry change in exciton wavefunctions

Abstract

Optical transitions in coupled InAs/InP self-assembled quantum wires are studied within the single-band effective mass approximation including effects due to strain. Both vertically and horizontally coupled quantum wires are investigated and the ground state, excited states and the photoluminescence peak energies are calculated. Where possible we compare with available photo-luminescence data from which it was possible to determine the height of the quantum wires. An anti-crossing of the energy of excited states is found for vertically coupled wires signaling a change of symmetry of the exciton wavefunction. This crossing is the signature of two different coupling regimes.