Electric-field-induced energy tuning of on-demand entangled-photon emission from self-assembled quantum dots

TL;DR

This paper demonstrates a method to electrically tune the energy of entangled-photon emission from quantum dots, advancing the development of solid-state quantum repeaters by enabling energy matching of entangled photons.

Contribution

The authors introduce an electrically-tunable quantum diode integrated with a piezoactuator to control entangled-photon emission energy from quantum dots, a novel approach for quantum communication.

Findings

Electric field can linearly tune the uniaxial stress in quantum dots.

The device achieves energy-tunable entangled-photon emission.

This method advances quantum repeater technology.

Abstract

The scalability of quantum dot based non-classical light sources relies on the control over their dissimilar emission energies. Electric fields offer a promising route to tune the quantum dot emission energy through the quantum-confined Stark effect. However, electric fields have been mostly used for tuning the energy of single-photon emission from quantum dots, while electrical control over the energy of entangled-photon emission, which is crucial for building a solid-state quantum repeater using indistinguishable entangled photons, has not been realized yet. Here, we present a method to achieve electrical control over the energy of entangled-photon emission from quantum dots. The device consists of an electrically-tunable quantum diode integrated onto a piezoactuator. We find that, through application of a vertical electric field, the critical uniaxial stress used to eliminate the fine-structure-splitting of quantum dots can be linearly tuned. This allows realization of a triggered source of energy-tunable entangled-photon emission, an important step towards a solid-state quantum repeater application.