Scatterings, Reactions and Quantum Many-Body States in Ultracold Molecules

现代量子技术使科学家能够在基态制备分子，并将这些分子冷却到几十纳开尔文的温度范围。这种超冷分子为科学家提供了前所未有的机会，可以探索以前无法实现的大量量子现象。超冷分子可以形成在其他系统中没有对应物的新量子物质，为研究量子化学提供新的平台，并可能成为实现量子信息处理的新的强大设备。在所有这些研究中，一个基本问题是理解分子之间的散射以及这种散射如何决定化学反应和新量子相的形成。 解决这个问题是这个项目的目标。 这项研究将探索分子之间的散射，并研究这些散射如何导致不同自由度之间的量子纠缠，从而导致新型拓扑量子物质的兴起。该小组将进一步实施散射作为操纵两体衰变的独特工具，并将探索在封闭系统中无法访问的损失分子的新的普遍关系。这些普适关系将使研究小组能够使用接触（稀释量子系统中的中心量）来追踪反应速率和多体相关性。该项目的成果将提供新的工具来控制超冷分子的损失，并为实验学家寻找新的超流体和其他量子多体相提供指导。此外，它还可以将接触和普遍关系的研究带入开放量子系统的新领域。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Modern quantum techniques have allowed scientists to prepare molecules in their ground states and cool these molecules down to a temperature regime of a few tens of nanokelvin. Such ultracold molecules offer scientists unprecedented opportunities to explore a vast range of quantum phenomena unattainable before. Ultracold molecules could form new quantum matter that has no counterparts in other systems, give rise to a new platform for studying quantum chemistry, and potentially serve as a new powerful apparatus to implement quantum information processing. In all of these studies, a fundamental issue is to understand scatterings between molecules and how such scatterings determine the chemical reactions and the formation of novel quantum phases. Addressing this issue is the goal of this project. This research will explore scatterings between molecules and study how these scatterings lead to quantum entanglement between different degrees of freedom and consequently the rise of novel topological quantum matter. The group will further implement the scatterings as a unique tool to manipulate two-body decays and will explore new universal relations for molecules with losses, which are inaccessible in closed systems. These universal relations will allow the team to trace both the reaction rate and many-body correlations using contacts, the central quantity in dilute quantum systems. The outcome of this project will deliver new tools to control losses of ultracold molecules and provide guidance for experimentalists to search for novel superfluids and other quantum many-body phases. Furthermore, it could bring the research of contacts and universal relations to a new domain of open quantum systems.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.