Enhancing the measurement signal from solid state quantum sensors such as the nitrogen-vacancy (NV) center in diamond is an important challenge for sensing and imaging of condensed matter systems. Here we design and fabricate diamond scanning probes with a truncated parabolic profile that optimizes the photonic signal from single, near-surface, embedded NV centers, forming a high-sensitivity probe for nanoscale magnetic field imaging. These structures operate over the full NV photoluminescence spectrum with the emission being directed into a measured numerical aperture of 0.44. Furthermore, they yield a median saturation count rate of , a $5$-fold improvement in measurement signal over the state-of-the art in scanning-probe based NV sensors. We additionally introduce a charge-state registered pulsed excitation method for measuring the detection efficiency of photons from the NV’s metrologically-relevant negative charge state, finding an overall detection efficiency of $12\%$. We demonstrate the excellent properties of these diamond scanning probes by imaging thin-film ferromagnetic stripes with a spatial resolution better than .

中文翻译：

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抛物线形金刚石扫描探头，用于单轴磁场成像

增强来自固态量子传感器（例如钻石中的氮空位（NV）中心）的测量信号，对于传感和成像凝聚态系统来说是一项重要的挑战。在这里，我们设计和制造出具有截顶抛物线轮廓的钻石扫描探针，该探针可以优化来自单个，近表面，嵌入式NV中心的光子信号，从而形成用于纳米级磁场成像的高灵敏度探针。这些结构在整个NV光致发光光谱上运行，并且将发射定向到测量的0.44的数值孔径中。此外，它们得出的中值饱和计数率为$5$与基于扫描探针的NV传感器相比，测量信号的改进程度达到了最新水平。我们还引入了一种电荷状态配准脉冲激励方法，用于测量NV计量相关的负电荷状态对光子的检测效率，得出总的检测效率为$12％$。我们通过对薄膜铁磁条进行成像来证明这些金刚石扫描探针的出色性能，其空间分辨率优于。