The emergence of controllable quantum systems has led to exciting applications for quantum computation, communication, and metrology. Among the many candidate systems, silicon carbide has attracted interest as a solid-state quantum platform in a technologically mature semiconductor material. When one creates atomic defects in silicon carbide lattice, individual electrons become trapped in isolated energy levels in the band gap. These electron spins can then be optically initialized and read out while being coherently controlled through microwave frequency fields. This interface between spin and photon quantum states provides exciting opportunities for creating remote entanglement on a macroscopic length scale. This thesis discusses the foundations of the divacancy in silicon carbide as a spin qubit and then presents the photonic enhancement of this system. More specifically, nanoscale photonic crystal cavities in silicon carbide are fabricated in order to modify the divacancy's zero-phonon line optical emission. This is vital for facilitating spin-photon and spin-spin entanglement protocols which rely on the emission of indistinguishable photons without losing coherence to phonons emitted into the lattice. A combination of electron-beam lithography and photoelectrochemical etching is employed to create suspended nanocavities in the 4H polytype. The combination of this structure with a centralized divacancy forms the foundational atom-cavity system studied in cavity quantum electrodynamics. As predicted from interactions with the cavity mode, a substantial Purcell enhancement of the divacancy zero-phonon line and a reduced excited state lifetime are observed. Additionally, we demonstrate spin control and coherence in these devices for the first time. More broadly, the cavity-emitter interactions in this system allow us to study transduction between spin and photonic degrees of freedom and provide a first step towards next generation hybrid devices.




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