Variable-density imaging of high concentration of NV centers with three-dimensional optical scanning techniques at sub-micrometer scale in millimeter area

Abstract

In order to enhance the spin-dependent fluorescence signal coupled with outer fields, accurate positioning of the center of nitrogen-vacancy (NV) in bulk diamond is important in enhancing the sensitivity of the solid-state quantum magnetometry. In this paper, we have developed a new approach of three-dimensional optical scanning techniques for the imaging of variable-density of high concentration of NV centers in the interior of the diamond at the micrometer scale. The research defined the definite trajectories of electrons with different energies to generate NV– centers in diamond based on Monte-Carlo simulation results. Moreover, it also confirmed experimentally that the accurate location for the center of NV– in the diamond is at the depth of 100 μm, using three-dimensional optical vertical scanning techniques. This research paves the way to produce various depth-confined NV centers, with high coherence, important in wide-field magnetometry applications.