基于Feshbach共振结合光泵浦技术的超冷钠铯极性分子高效制备实验研究

超冷分子物理的理论和实验研究有利地促进了多体物理，分子量子态操控，超冷化学等诸多前沿领域的快速发展。异核超冷基态极性分子作为新的研究平台已成为继超冷原子之后近年来国际上的研究热点。超冷钠铯分子作为研究平台的优势尤为突出，但是它的密集制备问题一直没有被解决。本项目以现有的Na，Cs玻色爱因斯坦凝聚为实验基础，提出Feshbach磁缔合结合光泵浦实现超冷钠铯分子密集制备的方案。该方案拟通过Feshbach缔合原理获得弱束缚的钠铯Feshbach分子，宽带光泵浦主动实现基态振转钠铯分子的持续积累。通过本方案将研究Na-Cs碰撞核间散射长度随磁场变化的物理机制以及泵浦光作用下超冷分子跃迁的动力学行为。本项目制备得到的密集超冷钠铯极性分子将为基于超冷极性分子的前沿科学研究提供良好的研究平台，同时本项目采用的实验方案也将为其他超冷极性分子的高效制备提供了新的途径。

The theoretical and experimental progress of ultracold molecules physics has efficiently promote the development of many fields such as novel many-body physics, molecular state manipulation, ultracold chemistry, and so on. Heteronuclear polar ground-state molecules serve as a new platform have attracted considerable attention in recent years after ultracold atoms. The ultracold NaCs molecule is an excellent research platform, but, its intensive preparation has not been solved. In this project , taking advantage of the scheme of Feshbach magnetic association and optical pumping, we intend to realize the efficient preparation of ultracold NaCs molecules based on Na, Cs Bose Einstein Condensation. The weakly bound Feshbach NaCs molecules will be realized by the Feshbach magnetic association,and the ground state molecules will be continuous accumulation under the broadband optical pumping. We will also research the physical mechanism for the changes of Na-Cs internuclear scattering length with different magnetic fields and the dynamic behavior of ultracold atomic transition under the action of pump light. Therefore, the implementation of the program will get high-quality molecular samples for the scientific research and pave a new way to the production of ultracold polar molecules.