Aleman, BenjaminKlaiss, Rachael2024-01-092024-01-092024-01-09https://hdl.handle.net/1794/29179Integrated quantum information technologies such as photonic circuits, quantum transducers, and magnetic sensors require robust single-photon sources in precise locations. Solid-state single photon emitters (SPEs) hosted by mid-bandgap defects in 2D material hexagonal boron nitride (hBN) are bright and stable at room temperature and demonstrate strong coupling to external fields, making them desirable candidates for quantum device applications. However, the specific atomic structure of hBN SPEs remains unidentified, making deterministic engineering a challenge. While recent studies have narrowed the range of possible defect candidates by demonstrating the role of carbon in hBN SPEs, the methods to engineer carbon-based defects in hBN either produce randomly located emitters or require bottom-up crystal growth on structured substrates. We achieved patterned arrays of SPEs via focused ion beam (FIB) milling followed by chemical vapor deposition (CVD) of nanocrystalline graphite source for carbon diffusion, and found that both techniques are necessary for significant and repeatable creation of SPEs. This technique creates localized emitters with ten times the yield of carbon annealing alone. Furthermore, by adjusting the parameters of FIB exposure time and carbon annealing time, we found multiple different parameter combinations that successfully created SPEs, demonstrating the adjustability of this technique based on device application requirements. Additionally, we performed atomic force microscopy to characterize the surface morphology of hBN regions patterned by Ga+ FIB to create SPEs at a range of ion doses and found that material swelling is strongly correlated to successful SPE creation. Furthermore, we simulated vacancy and impurity profiles to elucidate how Ga+ FIB patterning induces lattice damage in the form of vacancies, structural voids, and amorphous layers, creating a diffusion barrier to control the introduction of carbon impurities to engineer isolated SPEs with high resolution of process control. Our results provide novel insight into the formation of hBN SPEs created by high-energy, heavy-ion FIB that can be leveraged for monolithic hBN photonic devices and a wide range of low-dimensional solid-state SPE hosts. This dissertation includes previously published and unpublished coauthored material.en-USAll Rights Reserved.2D materialsDefect engineeringMaterials characterizationSingle photon sourcesElectronic Thesis or Dissertation