Ultracold mixtures of Cs and Yb atoms

本项目研究的是Cs和Yb原子在光学阱和晶格中的超冷和量子简并混合物。Cs和Yb具有截然不同的原子结构，这为超冷物理实验开辟了新的机会。铯有一个价电子，对磁势很敏感。除此之外，这导致了广泛的费什巴赫共振，允许控制种内相互作用。相比之下，Yb在一个封闭的壳层中有两个价电子，这使得Yb对磁势不敏感，并导致适合激光冷却到超冷温度的窄互合线。此外，Yb有几个适合研究的稳定同位素，扩大了实验可能性的范围，并允许与Cs制备玻色-玻色和玻色-费米混合物。最后，Cs和Yb中不同的跃迁波长允许用光场对特定物种进行捕获和操纵。所有这些性质都将在Cs和Yb的新物理研究中得到利用。具体来说，该项目的目标是在液滴阶段对气体进行高分辨率成像，在液滴阶段，平均场效应可以稳定系统。

This project concerns the study of ultracold and quantum degenerate mixtures of Cs and Yb atoms confined in optical traps and lattices. Cs and Yb have contrasting atomic structure that opens up new opportunities in the context of ultracold physics experiments. Cs has a single valence electron making it sensitive to magnetic potentials. Amongst other things this leads to broad Feshbach resonances that allow the control of intraspecies interactions. In contrast Yb has two valence electrons in a closed shell, making Yb insensitive to magnetic potentials and leading to narrow intercombination lines suitable for laser cooling to ultracold temperatures. Moreover, Yb has several stable isotopes suitable for study, extending the range of experimental possibilities and allowing for the preparation of Bose-Bose and Bose-Fermi mixtures with Cs. Finally the different transition wavelengths in Cs and Yb allow for species-specific trapping and manipulation with optical fields. All of these properties will be exploited in the study of new physics with Cs and Yb. Specifically the project targets high-resolution imaging of the gas in the droplet phase where beyond mean-field effects stabilise the system.