Quantum Transport in Strongly Interacting Fermi Gases

强相互作用费米气体中的量子输运

• 批准号: 1067873
• 负责人: John Thomas
• 金额: $ 53.58万
• 依托单位: North Carolina State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-08-15 至 2015-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1067873&HistoricalAwards=false
• 关键词: Quantum; Transport; Strongly; Interacting; Fermi

This program experimentally studies an optically-trapped, strongly interacting Fermi gas of Li(6) atoms as a model of universal quantum transport. This system offers unprecedented opportunities to test theoretical techniques that cross interdisciplinary boundaries, from condensed matter to nuclear matter. Measurements in ultracold Fermi gases now unite the coldest matter in the universe to the hottest matter, a quark-gluon plasma produced in gold ion collisions, which is comparable to the state of matter that existed microseconds after the Big Bang. Remarkably, both systems are found to be nearly 'perfect' fluids, in the context of a recent conjecture derived using string theory methods, with a similar ratio of viscosity to entropy density, despite a difference in temperature of 19 orders of magnitude and a difference in density of 25 orders of magnitude. The proposed tabletop experiments impact theories of strong interactions in intellectual disciplines well outside atomic physics, including materials science and condensed matter physics (superconductivity), nuclear physics (nuclear matter, quark-gluon plasma), high-energy physics (effective theories of strong interactions), and astrophysics (compact stellar objects). The proposed research may have practical impact in helping to determine whether it is possible to create super-high temperature nearly perfect conductors based on normal fluids, which would operate far above room temperature--materials that would enable energy-saving power lines and magnetically levitated trains. For this reason, the proposed program fits very well into national initiatives on energy and materials science.

本项目实验研究了Li（6）原子的光阱、强相互作用费米气体作为普适量子输运模型。该系统提供了前所未有的机会来测试跨学科边界的理论技术，从凝聚态物质到核物质。现在，对超冷费米气体的测量将宇宙中最冷的物质与最热的物质结合在一起，这是一种在金离子碰撞中产生的夸克-胶子等离子体，与大爆炸后微秒存在的物质状态相当。值得注意的是，这两个系统都被发现是几乎“完美”的流体，在最近的一个猜想的背景下，使用弦理论的方法，具有相似的粘度比熵密度，尽管在19个数量级的温度和密度的差异25个数量级。拟议的桌面实验影响了原子物理学以外的知识学科中的强相互作用理论，包括材料科学和凝聚态物理学（超导性），核物理学（核物质，夸克胶子等离子体），高能物理学（强相互作用的有效理论）和天体物理学（紧凑的恒星物体）。拟议中的研究可能会产生实际影响，有助于确定是否有可能创造基于正常流体的超高温近乎完美的导体，这种导体将在远高于室温的温度下工作-这种材料将使节能电力线和磁悬浮列车成为可能。出于这个原因，拟议的计划非常适合能源和材料科学的国家倡议。