Optimal electro-mechanical control of the excitonic fine structures of droplet epitaxial quantum dots

Abstract

The intrinsic fine structure splittings (FSSs) of the exciton states of semiconductor quantum dots (QDs) are known to be the major obstacle for realizing the QD-based entangled photon pair emitters. In this study, we present a theoretical and computational investigation of the excitonic fine structures of droplet-epitaxial (DE) GaAs/AlGaAs QDs under the electro-mechanical control of micro-machined piezoelectricity actuators. From the group theory analysis with numerical confirmation based on the developed exciton theory, we reveal the general principle for the optimal design of micro-machined actuators whose application on to an elongated QD can certainly suppress its FSS. We show that the use of two independently tuning stresses is sufficient to achieve the FSS-elimination but is not always necessary as widely deemed. The use of a single tuning stress to eliminate the FSS of an elongated QD is possible as long as the crystal structure of the actuator material is in coincidence with that of the QD. As a feasible example, we show that a {\it single} symmetric bi-axial stress naturally generated from the $(001)$ PMN-PT actuator can be used as a single tuning knob to make the full FSS-elimination for elongated DE GaAs QDs.

arXiv comment6 figures

References in corpus (18)

• Quantum entanglement
• Entangled Photon Pairs from Semiconductor Quantum Dots
• On-demand generation of indistinguishable polarization-entangled photon pairs
• Improved fidelity of triggered entangled photons from single quantum dots
• Highly indistinguishable and strongly entangled photons from symmetric GaAs quantum dots
• Electric-field-induced coherent coupling of the exciton states in a single quantum dot
• Magnetic-field-induced reduction of the exciton polarization splitting in InAs quantum dots
• Symmetric quantum dots as efficient sources of highly entangled photons
• Strain-tunable entangled-light-emitting diodes with high yield and fast operation speed
• Energy-tunable sources of entangled photons: a viable concept for solid-state-based quantum relays
• Strain-Tuning of the Optical Properties of Semiconductor Nanomaterials by Integration onto Piezoelectric Actuators
• Exciton polarization, fine structure splitting and quantum dot asymmetry under uniaxial stress
• Highly-reduced Fine-structure splitting in InAs/InP quantum dots offering efficient on-demand 1.55 $\mu$m entangled photon emitter
• Theory of exciton fine structure in semiconductor quantum dots: quantum dot anisotropy and lateral electric field
• Supercoupling between heavy-hole and light-hole states in self-assembled quantum dots
• Conquer the fine structure splitting of excitons in self-assembled InAs/GaAs quantum dots via combined stresses
• Energy-Tunable Quantum Dot with Minimal Fine Structure Created by Using Simultaneous Electric and Magnetic Fields
• Mechanically induced pseudo-magnetic fields in the excitonic fine structures of droplet epitaxial quantum dots