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We demonstrate a self-aligned lithographic technique for precision generation of nitrogen vacancy (NV) centers within photonic nanostructures on bulk diamond substrates. The process relies on a lithographic mask with nanoscale implantation apertures for NV creation, together with larger features for producing waveguides and photonic nanocavities. This mask allows targeted nitrogen ion implantation, and precision dry etching of nanostructures on bulk diamond. We demonstrate high-yield generation of single NVs at pre-determined nanoscale target regions on suspended diamond waveguides. We report implantation into the mode maximum of diamond photonic crystal nanocavities with a single-NV per cavity yield of ∼26% and Purcell induced intensity enhancement of the zero-phonon line. The generation of NV centers aligned with diamond photonic structures marks an important tool for scalable production of optically coupled spin memories.

The capability to embed self-assembled quantum dots (QDs) at predefined positions in nanophotonic structures is key to the development of complex quantum photonic architectures. Here, we demonstrate that QDs can be deterministically positioned in nanophotonic waveguides by pre-locating QDs relative to a global reference frame using micro-photoluminescence ($\mu$PL) spectroscopy. After nanofabrication, $\mu$PL images reveal misalignments between the central axis of the waveguide and the embedded QD of only $(9\pm46$) nm and $(1\pm33$) nm, for QDs embedded in undoped and doped membranes, respectively. A priori knowledge of the QD positions allows us to study the spectral changes introduced by nanofabrication. We record average spectral shifts ranging from 0.1 to 1.1 nm, indicating that the fabrication-induced shifts can generally be compensated by electrical or thermal tuning of the QDs. Finally, we quantify the effects of the nanofabrication on the polarizability, the permanent dipole moment and the emission frequency at vanishing electric field of different QD charge states, finding that these changes are constant down to QD-surface separations of only 70 nm. Consequently, our approach deterministically integrates QDs into nanophotonic waveguides whose light-fields contain nanoscale structure and whose group index varies at the nanometer level., Comment: 26 pages, 9 figures. Updated version of the manuscript, with new appendices and new figures