Pennacchietti, Matteo2026-05-192026-05-192026-05-192026-05-12https://hdl.handle.net/10012/23340Quantum technologies, such as quantum computing and quantum networks, are a rapidly developing new frontier in information technology, promising capabilities exceeding those of classical devices. Single particles of light, known as photons, are an important component for realising these quantum technologies, given that they can carry quantum information, known as qubits, over long distances. Generating single photons is possible using quantum emitters, which act as interfaces between light and matter—linking flying qubits (photons) with stationary qubits (such as electron spins). Semiconductor quantum dots (QDs) are a promising example of such quantum emitters, offering benefits such as high brightness, controllable emission wavelengths including in the telecom bands, and the scalable integration into photonic nanostructures for enhanced light-matter interactions. Among the many available QD devices, nanowire quantum dots (NWQDs) are a particularly attractive platform as they offer deterministic positioning of QDs into tapered photonic waveguides for high brightness and a Gaussian emission profile. In this thesis, we develop these NWQDs as an entangled photon source (EPS) for quantum networks and as a platform for waveguide quantum electrodynamics (wQED). In chapter 5, we focus on using the NWQD as an EPS using the biexciton-exciton cascade under two-photon excitation (TPE). We show that by utilising fast single photon detectors, the NWQD can generate entangled photon pairs with∼98% fidelity. In addition, we demonstrate that the exciton fine structure splitting does not degrade the entanglement generated by the QD if fast single photon detectors are used. We further enhance the performance of the NWQDs in chapter 6 by developing a novel pick-and-place technique to transfer the nanowires onto pre-fabricated templates. We fabricated two NWQD devices using the transfer method: a NWQD on a gold mirror with an estimated single photon extraction efficiency of∼73%; and a NWQD between quadrupolar gates capable of tuning the QD emission wavelength by∼3 GHz. Finally, in chapter 7, we explore the potential of the NWQD as a platform for wQED where there is a strong interaction between the QD and photons in the single waveguide mode. We developed a mode-matching technique to couple ∼95% of a free space laser drive field into the fundamental mode of the nanowire waveguide. With this mode matching technique we performed resonance fluorescence in the Heitler (weak drive) regime, and observed the reflection of single photons from the QD. Taken together, the findings presented in this thesis demonstrate an enhancement of the NWQD platform’s performance and highlight its potential as a complete quantum emitter platform for quantum photonic technology.enDoctoral Thesis