Perfect preferential orientation of nitrogen-vacancy defects in a   synthetic diamond sample
  We show that the orientation of nitrogen-vacancy (NV) defects in diamond can be efficiently controlled through chemical vapor deposition (CVD) growth on a (111)-oriented diamond substrate. More precisely, we demonstrate that spontaneously generated NV defects are oriented with a ~ 97 % probability along the [111] axis, corresponding to the most appealing orientation among the four possible crystallographic axes. Such a nearly perfect preferential orientation is explained by analyzing the diamond growth mechanism on a (111)-oriented substrate and could be extended to other types of defects. This work is a significant step towards the design of optimized diamond samples for quantum information and sensing applications. 
M. Lesik, J.-P. Tetienne, A. Tallaire, J. Achard, V. Mille, A.   Gicquel, J.-F. Roch and V. Jacques
cond-mat.mtrl-sci