  Atomic defects in wide band gap materials show great promise for development
of a new generation of quantum information technologies, but have been hampered
by the inability to produce and engineer the defects in a controlled way. The
nitrogen-vacancy (NV) color center in diamond is one of the foremost
candidates, with single defects allowing optical addressing of electron spin
and nuclear spin degrees of freedom with potential for applications in advanced
sensing and computing. Here we demonstrate a method for the deterministic
writing of individual NV centers at selected locations with high positioning
accuracy using laser processing with online fluorescence feedback. This method
provides a new tool for the fabrication of engineered materials and devices for
quantum technologies and offers insight into the diffusion dynamics of point
defects in solids.
