Lithium-rubidium gas mixtures and molecules

在过去的二十年里，世界各地的许多研究小组已经生产和研究了元素超冷原子气体，即温度仅高于零的百万分之一或十亿分之一的气体，由周期表上单一元素的原子组成。 这些超冷气体实验的应用大多是科学的，探索与量子力学和多体系统物理学相关的基本现象，但也越来越多地具有技术实用性，例如开发测量加速度，旋转，力和电磁场的传感器的努力非常高的精度。 该项目将通过研究由两种不同元素的原子组成的量子气体来扩展这项工作。 在同一实验中将两种气体结合起来，可以研究更广泛的量子现象。 此外，这种结合能够产生分子的超冷气体，这些分子是通过将两个原子从两种元素的原子气体结合在一起而形成的。 分子对外场的反应和分子之间的反应与原子不同。 相应地，由分子气体组成的量子力学系统将显示出与原子气体不同的量子现象，也可以用于与原子不同类型的传感器。更具体地说，本项目的重点是由锂和铷原子组成的气体。 一个两个元素的超冷原子气体将被用来研究超冷气体中的磁化顺序和动力学的自旋自由度是允许动态演变。 这两种元素的质量相差很大，这将允许在周期性光学势中研究重原子和轻原子之间的相互作用。 最后，我们将研究锂和铷的光缔合作用。 该项目旨在实现单点分辨率，并控制被困在光学晶格中的原子的光缔合和光解离。

In the last two decades, numerous research groups worldwide have produced and studied elemental ultracold atomic gases, i.e. gases at temperatures just a millionth or billionth above absolve zero and composed of atoms from a single element on the periodic table. The applications of these ultracold gas experiments have been mostly scientific, exploring basic phenomena associated with quantum mechanics and the physics of many-body systems, but also increasingly of technological utility, such as efforts to develop sensors that measure acceleration, rotation, forces, and electromagnetic fields with very high precision. This project will expand on this work by studying quantum gases composed of atoms of two different elements. The combination of the two gases in the same experiment allows for studies of a wider range of quantum phenomena. Moreover, the combination enables the creation of ultracold gases of molecules, which are formed by binding together two atoms from the two-element atomic gas. Molecules respond differently than atoms to external fields and to each other. Correspondingly, quantum mechanical systems composed of molecular gases will display different quantum phenomena than atomic gases, and can also serve for different types of sensors than do atoms.More specifically, this project focuses on gases composed of both lithium and rubidium atoms. A two-element ultracold atomic gas will be used to study magnetization order and dynamics in ultracold gases for which the spin degree of freedom is allowed to evolve dynamically. The largely different masses of the two elements will allow for studies of interactions between heavy and light atoms within periodic optical potentials. Finally, the photoassociation of lithium and rubidium into heteronuclear molecules will be investigated. The project aims to achieve single-site resolution and control over photoassociation and photodissociation of atoms trapped within optical lattices.