We report on the characterization of the angular-dependent emission of single-photon emitters based on single nitrogen-vacancy (NV-) centers in nanodiamond at room temperature. A theoretical model for the calculation of the angular emission patterns of such an NV-center at a dielectric interface will be presented. For the first time, the orientation of the NV-centers in nanodiamond was determined from back focal plane images of NV-centers and by comparison of the theoretical and experimental angular emission pattern. Furthermore, the orientation of the NV-centers was also obtained from measurements of the fluorescence intensity in dependence on the polarization angle of the linearly polarized excitation laser. The results of these measurements are in good agreement. Moreover, the collection efficiency in this setup was calculated to be higher than 80% using the model of the angular emission of the NV-centers.

中文翻译：

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纳米金刚石中氮空位中心随角度发射的表征

我们报告了室温下基于纳米金刚石中单个氮空位 (NV-) 中心的单光子发射器的角度相关发射的表征。将介绍计算这种 NV 中心在介电界面处的角发射模式的理论模型。首次通过 NV 中心的后焦平面图像以及理论和实验角发射模式的比较来确定纳米金刚石中 NV 中心的方向。此外，NV 中心的取向也从依赖于线性偏振激发激光的偏振角的荧光强度的测量中获得。这些测量的结果非常一致。而且，