超冷碱金属原子-双原子分子反应研究是目前超冷分子实验的一大热点。许多该类型分子体系的基态和第一电子激发态之间存在锥形交叉，因此反应过程中很可能存在显著的几何相位效应。遗憾的是，受限于计算难度，目前还没有相关量子动力学研究的报道。本项目旨在探究超冷碱金属原子-双原子分子反应中几何相位效应的存在，并详细揭示反应过程中几何相位效应的本质，从而为未来利用外加电磁场或是特定自旋态的反应物控制类似反应的开启或是关闭提供可能。不仅如此，本项目的成果也将有助于实验上对碱金属分子的蒸发冷却工作。

One of the research focuses of current ultracold molecule experiments is the study of ultracold alkali-metal atom-diatom reaction. In most of such molecule systems a conical intersection occurs between ground and first excited electronic states. As a result, geometric phase (GP) effects may be strong in the reaction process. Unfortunately, there are few quantum dynamics calculations have been performed for these reactions because of its daunting computational cost. This program is designed to explore the existence of the GP effects in the ultracold alkali-metal atom-diatom reaction, and to reveal explicitly the nature of the GP effects in the reaction process. Our work will open up possibilities to experimentally switch on or off the reactivity with the application of external electric and magnetic fields or nuclear-spin-conserved reactants. In addition, our work will facilitate the evaporative cooling experiments of ultracold alkali-metal molecules.