A Vertically Loaded Diamond Microdisk Resonator (VLDMoRt) for Quantum Networks

We propose and optimize a vertically-loaded diamond microdisk resonator (VLDMoRt) coupled to a nitrogen-vacancy (NV) center in diamond for efficient collection of fluorescence emission into low numerical aperture (NA) free-space modes. The VLDMoRt achieves a Purcell enhancement of 172 with 39% of the emitted light collected within a NA of 0.6, leading to a total external spin-photon collection efficiency of 0.33. As the design is compatible with established nanofabrication techniques and couples to low-NA modes accessible by cryogenic free-space optical systems, it is a promising avenue for increasing the efficiency and scalability of quantum devices based on diamond quantum emitters. © 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement