Open microcavities for cavity-enhanced quantum network nodes with diamond color centers

Building efficient interfaces between matter spin qubits and optical photons is key for realizing quantum networks. Color centers in diamond are promising matter qubits due to their long spin coherence times and spin register capabilities in combination with spin-state selective optical transitions. Open microcavities can serve as efficient spin-photon interfaces by Purcell-enhancing the color centers optical transitions. We realized a fiber-based low-temperature microcavity setup with high passive stability and microwave integration. This setup is used to Purcell-enhance Tin-Vacancy centers, demonstrating quantum non-linear effects in the coherent coupling regime. Furthermore, we will present our latest results on implementing a cavity-enhanced quantum network node based on Nitrogen-Vacancy centers.