Manipulating Spinor Quantum Gases

这个理论研究项目涉及原子在超冷低温区的量子力学性质。 每个原子都具有内部状态。 此外，原子像点粒子一样运动，因此可以用动量和角动量等量来表征。 在超冷状态下，原子内部自由度之间的相互作用，以及它们的外部运动，以及不同原子之间的相互作用，导致了许多有趣的现象，本研究项目旨在研究这些现象。 一方面，这些研究可以加深我们对原子--物质的基本组成部分--的基本性质的认识;另一方面，研究结果可以揭示超流体和超导体的奥秘，这些奥秘可能对未来的社会产生影响。 在第一个项目中，研究人员将专注于两种不同原子气体的相干混合物的性质。 由于物种间相互作用的存在，这种混合物的性质可能与单个气体的性质完全不同。 例如，纯气体的某些性质可能在混合物中被显著改变，并且纯气体中不存在的新的和奇异的量子相可能在混合物中出现。 此外，物种间的相互作用也提供了一个新的控制旋钮来操纵原子系统，这可能会开辟新的研究途径。 在第二个项目中，研究人员将考虑限制在一维空间中的超冷原子。 这样的系统通常在实验室中通过将原子捕获在细长的几何形状中来实现。 这样的限制可以极大地影响原子的量子特性。研究人员将开发新的理论工具，以帮助我们更好地理解一维超冷原子的新特性，特别是在强相互作用极限下，传统方法经常失败。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。

This theoretical research program concerns the quantum mechanical properties of atoms in the ultracold low temperature regime. Each atom possesses internal states. In addition, the atom moves like a point particle and hence can be characterized by such quantities as momentum and angular momentum. In the ultracold regime the interplay between the atomic internal degrees of freedom, and their external motion, as well as interactions between different atoms, leads to many intriguing phenomena which this research project aims to investigate. On the one hand, such studies can deepen our knowledge about the fundamental properties of atoms --- the basic building blocks of matter; on the other hand, the research results could shed light on the mysteries of superfluids and superconductors which may have future societal impact.This research program can be divided into two projects. In the first project, the researchers will focus on the properties of a coherent mixture of two different atomic gases. Due to the presence of the inter-species interaction, the properties of such a mixture can be quite different from those of an individual gas. For example, certain properties of the pure gas may be significantly modified in the mixture, and new and exotic quantum phases that do not exist in a pure gas may emerge in the mixture. Furthermore, the inter-species interaction also offers a new control knob to manipulate the atomic system which may open up new avenues of research. In the second project, the researchers will consider ultracold atoms confined into one dimensional space. Such a system has been routinely realized in the laboratories by trapping atoms in elongated geometries. Such confinement can greatly affect the quantum properties of the atom. The researchers will develop new theoretical tools to help us better understand the novel properties of ultracold atoms in one dimension, particularly in the strong interaction limit where conventional methods often fail.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.