Electro-elastic tuning of single particles in individual self-assembled quantum dots

TL;DR

This study demonstrates how uniaxial stress can precisely tune the electronic and optical properties of individual quantum dots, enabling resonance control for quantum device applications.

Contribution

It provides the first detailed measurement of uniaxial stress effects on single InGaAs quantum dots, including energy shifts and exciton tuning capabilities.

Findings

Significant single-particle energy tuning (~ -0.5 meV/MPa) under stress

Variable exciton energy tuning (+18 to -0.9 μeV/MPa) observed

Ability to tune multiple quantum dots into resonance on the same chip

Abstract

We investigate the effect of uniaxial stress on InGaAs quantum dots in a charge tunable device. Using Coulomb blockade and photoluminescence, we observe that significant tuning of single particle energies (~ -0.5 meV/MPa) leads to variable tuning of exciton energies (+18 to -0.9 micro-eV/MPa) under tensile stress. Modest tuning of the permanent dipole, Coulomb interaction and fine-structure splitting energies is also measured. We exploit the variable exciton response to tune multiple quantum dots on the same chip into resonance.