Enhanced Quantum Nano-Sources Based on Silicon-Vacancy Centers in Epitaxially Grown Diamond Nano-Pyramids

The negatively charged silicon-vacancy center (SiV) in diamond is a potential high-quality source of single-indistinguishable photons for quantum information processing and quantum electrodynamics applications[1]. Protected by inversion symmetry, the SiV possesses bright narrow-band and spectrally stable optical transition. However, when embedded in bulk diamond, this emitter suffers from relatively low extraction efficiency attributed to total internal reflection as well as nondeterministic location. On the other hand, its implementation in nanodiamonds or nanostructures prepared by a top-down approach can mitigate the issue of total internal reflection, but impeded by optical dephasing owing to their degraded surface quality.