Photoluminescence Spectroscopy of the Molecular Biexciton in Vertically Stacked Quantum Dot Pairs

TL;DR

This study investigates the photoluminescence spectra of molecular biexcitons in vertically stacked InAs/GaAs quantum dot pairs, demonstrating tunability via electric fields and structural design for potential nonlinear optical applications.

Contribution

It provides a detailed analysis of the molecular biexciton spectra in quantum dot pairs and introduces a model to describe their properties under various tuning conditions.

Findings

Spectra are well described by a few-level, few-particle molecular model.

Properties can be broadly modified by electric fields.

Structural design influences the optical properties significantly.

Abstract

We present photoluminescence studies of the molecular neutral biexciton-exciton spectra of individual vertically stacked InAs/GaAs quantum dot pairs. We tune either the hole or the electron levels of the two dots into tunneling resonances. The spectra are described well within a few-level, few-particle molecular model. Their properties can be modified broadly by an electric field and by structural design, which makes them highly attractive for controlling nonlinear optical properties.