The negatively charged nitrogen vacancy (NV^-) center ensembles in diamond have been demonstrated to be a promising platform for quantum metrology, but the poor fluorescence collection efficiency of a microscope objective limits the sensitivity of the NV^- based sensors. Here we present a method for increasing the collected fluorescence intensity with a total internal reflection (TIR) lens. The detected fluorescence intensity is increased by approximately a factor of 56 compared with detection using a microscope objective with NA = 0.55, leading to a collection efficiency of 47.7% ± 3.1%. The signal-to-noise ratio is improved by a factor of 7.6 using the TIR lens. The proposed method is of great significance for collecting fluorescence from NV^- centers in a large volume and can be used in weak fluorescence detection systems.

中文翻译：

---

用于NV的高效荧光收集^-钻石中心镶嵌

带负电的氮空位（NV ^- ）在钻石中心合奏已被证明是用于量子计量一个有前途的平台，但在显微镜物镜限制NV的灵敏度差荧光收集效率^-基于传感器。在这里，我们提出了一种使用全内反射（TIR）透镜提高收集的荧光强度的方法。与使用NA = 0.55的显微镜物镜进行检测相比，检测到的荧光强度提高了约56倍，导致收集效率为47.7％±3.1％。使用TIR透镜，信噪比提高了7.6倍。该方法是从NV收集荧光十分重要的意义^- 可以大量集中，并且可以在弱荧光检测系统中使用。