Abstract:The nitrogen-vacancy (NV) defect center in diamond is a system that has many promising properties for the implementation of scalable quantum networks. On the one hand, it possesses excellent spin coherence properties and allows for coupling to very long lived nuclear spin-based quantum memories. On the other hand, its atom-like optical transitions have enabled a variety of quantum-optics phenomena that are the building blocks of, for example, a quantum repeater node. These experiments include demonstrations of spin-photon entanglement and two-photon interference from remote NV centers. I will present recent and ongoing work toward incorporating NV centers into nanoscale optical devices. In particular, we implement diamond-based nano-cavities with low mode volume and high quality factors that contain NV centers with desirable optical properties. Such devices can become crucial components of a solid-state quantum network by acting as single-photon transistors and enabling strong coupling between the NV center and cavity photons.