Towards integrated scalable nanophotonic circuits

This thesis presents optical measurements used to explore nanophotonic circuits composed of III-V semiconductors with embedded quantum dots. The focus of this work is to investigate issues related to the scalability and performance of these structures. A technique to register the position of a quantum dot, relative to pre-fabricated registration markers, with the aid of a solid immersion lens, is developed. The variance in the repeatedly registered position of the quantum dot is shown to be significantly reduced as a result of the solid immersion lens, compared with positions registered without a solid immersion lens. The total error of the deterministic fabrication, using position registered quantum dots, is small when compared to the size of optical fields. Confirmation of this has been achieved through two independent methods. Re-registration of the position relative to deterministically positioned registration markers show that the total error of deterministic fabrication is small. Additionally, the demonstration of optical spin readout, via the deterministic positioning of a quantum dot at a chiral point of a suspended nanobeam waveguide, further confirms the positional accuracy of the technique. The demonstration of efficiently coupled single photons form an embedded quantum into a nanobeam waveguide, with enhanced coherence lengths due to resonant excitation, is achieved. A high level of resonant laser rejection is demonstrated due to the orthogonal excitation and waveguide propagation directions.