论文标题
氦离子植入剂量和退火对NV中心密集的近表面层的影响
Impact of helium ion implantation dose and annealing on dense near-surface layers of NV centers
论文作者
论文摘要
用氦离子植入钻石成为一种常见方法，可以创建数百个纳米米的NV中心的近表面层，用于高敏感性和成像应用。但是，最佳植入剂量和退火温度仍然是讨论的问题。在这项研究中，我们使用不同植入剂量的氦离子辐射的HPHT钻石，初始氮浓度为100 ppm，以产生200 nm厚的NV层。我们通过测量磁共振的荧光强度，对比度和线宽以及纵向和横向放松时间$ t_1 $ t_1 $和$ t_2 $，将先前认为的$ \ sim10^{12} $的最佳植入剂量与双剂量和三剂量进行比较。从这些直接测量中，我们还估计了P1和NV中心的浓度。此外，我们比较了经过三个随之而来的退火步骤的三个钻石样本，以量化在1100 $^{\ circ} $ C下处理的影响，该钻石的影响是在800 $^{\ circ} $ c下进行初始退火。通过将植入剂量增加三倍，我们使传感器的磁敏感性提高了$ 28 \ pm5 $％。通过将我们的结果投影到更高的植入剂量，我们表明可以进一步改善高达70％的剂量。同时，以1100 $^{\ circ} $ c的额外退火步骤仅提高敏感性6.6 $ \ pm $ 2.7％。
Implantation of diamonds with helium ions becomes a common method to create hundreds-nanometers-thick near-surface layers of NV centers for high-sensitivity sensing and imaging applications. However, optimal implantation dose and annealing temperature is still a matter of discussion. In this study, we irradiated HPHT diamonds with an initial nitrogen concentration of 100 ppm using different implantation doses of helium ions to create 200-nm thick NV layers. We compare a previously considered optimal implantation dose of $\sim10^{12}$ to double and triple doses by measuring fluorescence intensity, contrast, and linewidth of magnetic resonances, as well as longitudinal and transversal relaxation times $T_1$ and $T_2$. From these direct measurements we also estimate concentrations of P1 and NV centers. In addition, we compare the three diamond samples that underwent three consequent annealing steps to quantify the impact of processing at 1100 $^{\circ}$C, which follows initial annealing at 800 $^{\circ}$C. By tripling the implantation dose we have increased the magnetic sensitivity of our sensors by $28\pm5$ %. By projecting our results to higher implantation doses we show that a further improvement of up to 70 % may be achieved. At the same time, additional annealing steps at 1100 $^{\circ}$C improve the sensitivity only by 6.6 $\pm$ 2.7 %.
