Quantum Light Sources from Solid-State Emitters

Abstract

Quantum light generated by solid-state emitters has become a leading resource for photonic quantum technologies, combining deterministic emission with scalable on-chip integration. Practical deployment of these light sources requires characterising the light they produce, optically addressing them individually and ensuring light can be extracted efficiently from the solid-state host. In this thesis, we first study how the quantum nature of light can be characterised via its photon statistics. We then examine how to speed these measurements up, a necessity for the scalable characterisation of many emitters. We find that the use of multiplexed single-photon detectors offers a straightforward route to faster characterisation of quantum light sources via photon correlation measurements, while simultaneously providing additional information about the statistics of emitted photons. Next, we explore how to optically address individual emitters via confocal microscopy at cryogenic temperatures. We report the development of such a setup, demonstrating both widefield imaging and photoluminescence raster imaging of individual emitters. Finally, we engineer the diamond host to enhance photon extraction from embedded emitters, extending a previously reported fabrication process for photonic nanojet structures to (111)-oriented diamond. We confirm high-fidelity pattern transfer using scanning electron microscopy and profilometry, establishing that the adapted process is compatible with this orientation. Together, these results contribute to the characterisation, addressing and engineering capabilities required for the practical deployment of solid-state quantum emitters in quantum technologies.