No abstract

The negatively charged nitrogen-vacancy (NV  ) center in diamond is an attractive candidate for applications that range from magnetometry to quantum information processing. Here we show that only a fraction of the nitrogen (typically < 0.5 %) incorporated during homoepitaxial diamond growth by Chemical Vapor Deposition (CVD) is in the form of undecorated NV  centers. Furthermore, studies on CVD diamond grown on   110 oriented substrates show a near 100% preferential orientation of NV  centers along only the   111 and   111 directions, rather than the four possible orientations. The results indicate that NV centers grow in as units, as the diamond is deposited, rather than by migration and association of their components. The NV unit of the NVH  is similarly preferentially oriented, but it is not possible to determine whether this defect was formed by H capture at a preferentially aligned NV center or as a complete unit. Reducing the number of NV orientations from 4 orientations to 2 orientations should lead to increased optically-detected magnetic resonance contrast and thus improved magnetic sensitivity in ensemble-based magnetometry.

We report on electron paramagnetic resonance (EPR) studies of nitrogen doped diamond that has been (15)N enriched, electron irradiated and annealed. EPR spectra from two new nitrogen containing [Formula: see text] defects are detected and labelled WAR9 and WAR10. We show that the properties of these defects are consistent with them being the ⟨001⟩-nitrogen split interstitial and the ⟨001⟩-nitrogen split interstitial-⟨001⟩-carbon split interstitial pair, respectively. We also provide an explanation for why these defects have previously eluded discovery.