NSF-BSF: Universality Puzzles and Coherent Control of Efimov Physics with 7Li Atoms

这个项目将探索几个原子之间的相互作用，特别是在超低温条件下实现量子控制的方法，在超低温条件下，气体在自然界中成为量子力学。少数原子系统及其极端的非微扰相互作用给原子理论家带来了一些最大的挑战，并提供了许多机会来促进我们的科学知识，带来潜在的技术和基础影响。该项目代表了通过美国国家科学基金会(NSF)和美国-以色列双国科学基金会(BSF)进行的理论和实验合作。该项目的目标是开发理论工具，结合实验分析，将能够详细研究强相互作用量子气体的性质，重点是开发使用静态外场或电磁场来控制复杂的多通道碰撞动力学。一个具体的目标是探索7Li超冷量子气体，以了解与系统中Efimov态普适性的性质有关的令人费解的观察结果。这些研究将作为这次理论-实验合作的主要重点的基础，该合作涉及探索7Li超窄Feshbach共振和原子-二聚体混合物附近的新物理。将特别关注Efimov态的散射性质和寿命的确定，以及使7Li气体成为探索宇宙量子物理的独特系统的潜在物理机制。该项目还包括对少体过程实施相干控制的研究，这可以通过关闭少体损失来实现强相互作用气体的稳定，以及开辟控制三体相互作用和叠加态的方法，从而能够创建奇异的动力学制度。除此之外，对超冷原子相互作用的更深入了解可以在原子钟、量子信息科学和探索许多新的物质相方面产生应用。这项工作的主要教育影响来自于对研究生和本科生进行最先进的理论和计算研究技术的培训。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Interactions among a few atoms will be explored by this project, and in particular, ways to achieve quantum control in the regime of ultracold temperatures where a gas becomes quantum mechanical in nature. Few-atom systems with their extremely nonperturbative interactions pose some of the greatest challenges for atomic theorists and provide many opportunities to advance our scientific knowledge with potential technological and fundamental impacts. This project represents a theoretical and experimental collaboration via the US National Science Foundation (NSF) and the US-Israel Binational Science Foundation (BSF). The goal of the project is to develop the theoretical tools, which, combined with experimental analysis, will enable a detailed investigation of properties of strongly interacting quantum gases with a focal point on developing control of the complex multichannel collision dynamics using either a static external field or an electromagnetic field. A specific goal is to explore 7Li ultracold quantum gases to understand puzzling observations related to the nature of the universality of Efimov states in the system. These studies will serve as the base of the main focus of this theory-experiment collaboration, which involves the exploration of new physics near the 7Li ultra-narrow Feshbach resonance and atom-dimer mixtures. Particular attention will be given on the determination of the scattering properties and lifetime of Efimov states as well as the underlying physical mechanisms which make 7Li gases a unique system to explore universal quantum physics. The project also includes studies for the implementation of coherent control over few-body processes which can enable the stabilization of strongly interacting gases, by turning off few-body losses, as well as open up ways to control three-body interactions and superposition states, allowing for the creation of exotic dynamical regimes. Beyond that, a deeper understanding of the ultracold atom interactions can spawn applications to atomic clocks, quantum information science, and the exploration of many novel phases of matter. The key educational impact of this work derives from the training of graduate and undergraduate students in state-of-the-art theoretical and computational research techniques.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.