CAREER:Laser Cooling and Trapping of Beryllium: Frozen Plasmas and Precision Measurements

该职业奖支持对铍（Be）作为下一代光学原子钟的新候选元素以及产生超冷中性等离子体（离子和电子的超冷气体）的研究。原子钟在20世纪的科学和技术进步中发挥了重要作用，导致了全球定位、先进通信和粒子物理学基础理论测试等创新。下一代光学原子钟将扩展这些系统的功能，并将增强数据路由和通信的安全性，先进的基于地球和时空的导航，以及更精确地测试爱因斯坦的广义相对论。超冷中性等离子体（UCNPs）是激光产生的等离子体，扩展了传统等离子体物理的边界。 然而，对这些桌面超冷系统的研究有望大大提高我们对许多天体物理系统中发生的更热、更密集等离子体的理解。该项目的目标是激光冷却，捕获和光致电离中性原子铍，以使其可能用作光学频率标准，并在足够低的温度下产生UNCP，以便在系统内形成离子晶体，实际上冻结等离子体。 该奖项还将吸引和留住更多代表性不足的少数民族学生参加物理研究。 该项目将通过现有的亚拉巴马-伯明翰大学项目，让少数民族研究生、本科生和高中生参与Simien光谱学和激光冷却组的研究项目。此外，还将开展一些推广活动，通过在当地学校进行物理和化学演示，让K-12学生对科学和工程产生兴趣。该项目是一项实验计划，旨在研究原子铍的光谱、激光冷却和光电离特性，因为它与原子钟和超冷中性等离子体有关。Be是一种碱土金属元素，具有简单的内部结构，在光学区域中为中性原子和离子提供电偶极和互组合跃迁。 它是下一代频率标准和激光冷却，捕获和光电离产生超冷等离子体的一个有前途的候选人。特别是，光谱研究将涉及强电偶极跃迁的超精细结构的测量。本研究的目的是确定Be超精细常数，它定义了超精细峰的排序和磁偶极子和电四极相互作用对能量转移的贡献。这种光谱性质的测定对于实现铍的激光冷却和俘获是必要的。此外，激光冷却和捕获将被用来创建一个磁光阱，作为对互组合线进行精确测量的第一步。 它也将被用于光电离的研究，用于产生基于Be的频率标准和超冷中性等离子体，可以有效地激光冷却到强耦合制度。 该项目由等离子体物理计划，原子，分子和光学实验物理计划以及刺激竞争性研究的既定计划（EPSCoR）共同资助。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 CAREER award supports investigation of berillium (Be) as a new candidate element for the next generation of optical atomic clocks, as well as for producing an ultracold neutral plasma -- an ultracold gas of ions and electrons. Atomic clocks have been instrumental in the advancement of science and technology in the twentieth century, leading to innovations such as global positioning, advanced communications, and tests of fundamental theories of particle physics. A next generation optical atomic clock would extend the capabilities of these systems and will enable enhanced security for data routing and communications, advanced earth and space time-based navigation, and ever more precise testing of Einstein's Theory of General Relativity. Ultracold neutral plasmas (UCNPs) are laser produced plasmas that stretch the boundaries of traditional plasma physics. However, studies of these table-top ultracold systems are promising to greatly improve our understanding of much hotter and denser plasmas thought to occur in many astrophysical systems. The goal of this project is to laser cool, trap and photo-ionize neutral atomic beryllium for its potential use as an optical frequency standard, and to produce a UNCP at a sufficiently low temperature for ionic crystals to form inside the system, virtually freezing the plasma. This award will also make it possible to attract and retain more underrepresented minority students to physics studies. The project will involve minority graduate, undergraduate, and high school students via existing Univ. of Alabama - Birmingham programs to participate in research projects in the Simien Spectroscopy and Laser Cooling group. Additional outreach activities will aim to get K-12 students interested in science and engineering by performing physics and chemistry demonstrations at local schools in the region.This project is an experimental program directed towards investigation of spectroscopic, laser cooling, and photoionization properties of atomic beryllium as it relates to atomic clocks and ultracold neutral plasmas. Be is an alkaline earth element with a simple internal structure which provides for electric-dipole and intercombination transitions in the optical regions for both neutral atoms and ions. It is a promising candidate for next generation frequency standards and for laser cooling, trapping, and photo-ionization to produce an ultracold plasma. In particular, the spectroscopic studies will involve measurements of the hyperfine structure of strong electric dipole transitions. The objective of this study is to determine Be hyperfine constants, which define the ordering of the hyperfine peaks and contributions to the energy shifts from the magnetic dipole and electric quadrupole interactions. The determination of this spectroscopic property is necessary for implementing laser cooling and trapping of beryllium. In addition, laser cooling and trapping will be used to create a magneto-optical trap as the first step towards performing precision measurements on the intercombination lines. It will also be used for photoionization studies for generation of a Be based frequency standard and an ultracold neutral plasma that can be efficiently laser cooled into the strongly coupled regime. This project is jointly funded by the Plasma Physics program, the Atomic, Molecular and Optical Experimental Physics program, and the Established Program to Stimulate Competitive Research (EPSCoR).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.