We demonstrate single-site-resolved fluorescence imaging of ultracold $^{87}\mathrm{Rb}$ atoms in a triangular optical lattice by employing Raman sideband cooling. Combining a Raman transition at the D1 line and a photon scattering through an optical pumping of the D2 line, we obtain images with low background noise. The Bayesian optimisation of 11 experimental parameters for fluorescence imaging with Raman sideband cooling enables us to achieve single-atom detection with a high fidelity of $(96.3 \pm 1.3)$%. Single-atom and single-site resolved detection in a triangular optical lattice paves the way for the direct observation of spin correlations or entanglement in geometrically frustrated systems.

中文翻译：

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三角形光学晶格中超冷原子的单点分辨成像

我们通过使用拉曼边带冷却展示了三角形光学晶格中超冷 $^{87}\mathrm{Rb}$ 原子的单点分辨荧光成像。结合 D1 线的拉曼跃迁和通过 D2 线的光泵浦的光子散射，我们获得了具有低背景噪声的图像。使用拉曼边带冷却对荧光成像的 11 个实验参数进行贝叶斯优化，使我们能够以 $(96.3 \pm 1.3)$% 的高保真度实现单原子检测。三角形光学晶格中的单原子和单点分辨检测为直接观察几何受挫系统中的自旋相关性或纠缠铺平了道路。