We describe and characterize an experimental apparatus that has been used to study interactions between ultracold lithium atoms and ytterbium ions. The preparation of ultracold clouds of Li atoms is described as well as their subsequent transport and overlap with ${\mathrm{Yb}}^{+}$ ions trapped in a Paul trap. We show how the kinetic energy of the ion after interacting with the atoms can be obtained by laser spectroscopy. We analyze the dynamics of the buffer-gas-cooled ion after releasing the atoms, which indicates that background heating, due to electric-field noise, limits attainable buffer gas cooling temperatures. This effect can be mitigated by increasing the density of the Li gas in order to improve its cooling power. Imperfections in the Paul trap lead to so-called excess micromotion, which poses another limitation to the buffer gas cooling. We describe in detail how we measure and subsequently minimize excess micromotion in our setup. We measure the effect of excess micromotion on attainable ion temperatures after buffer gas cooling and compare this to molecular dynamics simulations, which describe the observed data very well.

中文翻译：

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研究捕获的Yb + –Li6超冷混合物的实验装置

我们描述并描述了一种已被用于研究超冷锂原子和离子之间相互作用的实验装置。描述了Li原子超冷云的制备及其随后的传输和与$b^{+}$离子被困在Paul阱中。我们展示了如何通过激光光谱获得离子与原子相互作用后的动能。我们在释放原子后分析了缓冲气体冷却离子的动力学，这表明由于电场噪声，背景加热限制了可达到的缓冲气体冷却温度。可以通过增加Li气体的密度以改善其冷却能力来减轻这种影响。Paul阱中的缺陷会导致所谓的超微运动，这对缓冲气体的冷却造成了另一个限制。我们详细描述了如何测量并随后最大程度地减少设置中的多余微动。我们测量缓冲气体冷却后过量微运动对可达到的离子温度的影响，并将其与分子动力学模拟进行比较，