The sensitivity of the nitrogen-vacancy (NV) color centers in diamond-based magnetometers strongly depends on the number of NV centers involved in the measurement. Unfortunately, an increasing concentration of NV centers leads to a decrease in their dephasing and coherence times if the nitrogen content exceeds a certain threshold level (approximately ${10}^{17}c{m}^{-3}$ or 0.6 ppm). Here, we demonstrate that this increased dephasing can be efficiently compensated for by optimizing the electron irradiation dose in postprocessing procedures in the vicinity of the threshold concentration, thus extending the range of possible useful concentrations of NV centers in diamonds with a natural carbon content.

金刚石磁力计中的氮空位（NV）颜色中心的灵敏度很大程度上取决于测量中涉及的NV中心的数量。不幸的是，如果氮含量超过一定的阈值水平（大约），NV中心浓度的增加会导致其相移和相干时间的减少。${10}^{17}C{米}^{--3}$或0.6 ppm）。在这里，我们证明可以通过在阈值浓度附近优化后处理程序中的电子辐照剂量来有效地补偿这种增加的相移，从而扩大了天然碳含量的钻石中NV中心的可能有用浓度范围。