Photonic Quantum Technologies with Strain-Free Artificial Atoms

Photons are an excellent platform to explore fundamental quantum properties without disturbance from the environment. They are also advantageous for applied topics such as quantum communication and simulation.

The prerequisite for exploiting photons in quantum science is producing and manipulating high-quality streams of entangled photons in a scalable setting. Yet, the progress on this front has been slow primarily due to shortcomings in material properties.

So far, only small states involving three photons have been demonstrated, and the quest of generating two-dimensional entanglement is untouched.

In this project, I will address the scalability problem employing an emerging class of artificial atoms named gallium arsenide quantum dots (GaAs QDs). Contrary to standard QDs, GaAs QDs are free from mechanical strain.

As a result, GaAs QDs have lower noise, and different GaAs QDs have similar optical properties; these are critical requirements for a scalable platform. We will use photonic nanostructures to flexibly interface GaAs QDs on a photonic chip. Such a scalable platform will be an invaluable contribution to photonic quantum technologies.

As an immediate outcome, we will use this platform to deliver three novel goals:1. Highly entangled states of photons with two-dimensional connectivity2. First experimental studies on the interaction between photons in a strongly non-linear medium3.

Pave the way towards quantum memories based on the collective states of nuclei in a QDThese achievements will be enabling contributions to quantum technologies.

Two-dimensional clusters of entangled photons are indispensable resources with immediate applications in quantum communication and will open new prospects for photonic quantum simulation.

Additionally, studying the interaction between photons in a strongly nonlinear medium will enable us to build number-resolving photon detectors, and in the longer term, may enable emulating many-body quantum systems on our platform.