A Program in Ultra-Low Temperature Atomic Physics

新型磁性材料在许多领域具有重要的应用价值。然而，磁性仍然有未解之谜，特别是在涉及强相互作用和粒子之间强关联的系统中。研究磁性材料的一种方法是在最简单的系统中实现磁性现象，这些系统被很好地控制和很好地表征。最简单的系统是超冷原子，它是非常稀薄的气体(比空气稀薄一百万倍)。在非常低的温度下，这些气体可以表现为液体、固体、金属、超导体或磁体。麻省理工学院的这项工作研究了三个不同系统中的量子磁性：光学晶格中的双组分玻色和费米气体，以及自由空间或光学晶格中离域费米子的所谓巡回铁磁性。这项工作解决了多体物理前沿的重要问题，并将对未来原子物理、凝聚态物理和多体理论的研究产生影响。利用超冷原子研究量子磁学，促进了玻色和费米强相互作用气体的理论工作，并将促进我们对宏观量子系统和磁性材料的理解。对磁性和超流性的深入了解可能会导致未来出现新材料和新器件。这项工作为几名本科生、研究生和博士后提供研究培训，并为他们在技术和科学领域的成功职业生涯做好准备。以前的学生和博士后继续在科学和技术领域找到杰出的职位。所有的研究都将在校园内进行，并将通过为本科生提供研究机会、参观实验室以及在课堂上用作物理基本概念的插图，完全整合到教学和教育中。通过他的公开演讲，Ketterle教授接触到了更多的普通观众。他经常为高中生做演讲，例如在麻省理工学院的年度RSI(研究暑期研究所)项目上，在麻省理工学院的TOPS(物理科学教学机会)项目上，以及在访问高中期间。Ketterle教授发起的另一项推广活动是原子量子流体虚拟杂志。

Novel magnetic materials are important for many applications. However, magnetism still has unresolved mysteries, especially in systems involving strong interactions and strong correlations between the particles. One approach to study magnetic materials is to realize magnetic phenomena in the simplest possible systems which are well controlled and well characterized. The simplest systems are ultracold atoms, which are very dilute gases (a million times less dilute than air). At very low temperatures, these gases can behave like liquids, solids, metals, superconductors, or magnets. The work at MIT studies quantum magnetism in three different systems: Two component Bose and Fermi gases in optical lattices, and so-called itinerant ferromagnetism of delocalized fermions in free space or in optical lattices. This work addresses important questions at the frontier of many-body physics and will have impact on future research in atomic physics, condensed matter physics and many-body theory.Broader impact. Research on quantum magnetism using ultracold atoms stimulates theoretical work on strongly interacting Bose and Fermi gases and will advance our understanding of macroscopic quantum systems and of magnetic materials. A deeper understanding of magnetism and superfluidity may lead to new materials and novel devices in the future. This work provides research training for several undergraduates, graduate students, and postdocs, and prepares them for successful careers in technology and science. Former students and postdocs continue to find distinguished positions in the area of science and technology. All the research will be performed on campus and will be fully integrated in teaching and education, through research opportunities for undergraduates, lab tours, and by being used in lectures as illustrations for basic concepts in physics. Through his public lectures, Prof. Ketterle reaches out to more general audiences. He regularly gives talks for high school students, e.g. at the annual RSI (Research Summer Institute) program at MIT, at the TOPS (Teaching opportunities in the physical sciences) program at MIT, and during visits to high schools. An additional outreach activity initiated by Prof. Ketterle is the Virtual Journal of Atomic Quantum Fluids.