Ultracold Strontium

锶最近成为实验和理论原子物理小组研究激光冷却、光频率标准、冷碰撞和量子简并气体的焦点。这个实验研究项目的重点是确定碰撞特性和基态势，这将为锶应用的持续发展奠定基础，例如优化蒸发冷却或碰撞时钟偏移的散射长度，或与原子结构计算进行比较的远程势参数。第一个实验将是双原子锶分子基态电位最高水平的双色光结合光谱。之后的实验将利用这些信息来探索光诱导的费什巴赫共振，并创造量子简并气体。锶玻色-爱因斯坦凝聚不会简单地证明另一个凝聚原子。光学诱导的费什巴赫共振将允许在比磁性费什巴赫共振更快的时间尺度或更细的空间尺度上灵活地操纵原子-原子相互作用。玻色子同位素缺乏超精细结构可能使凝聚体对环境扰动不敏感，更适合原子光学和干涉测量应用。该计划的更广泛影响包括对学生的教育以及对多样性的努力。

Strontium has recently become the focus of intense work by experimental and theoretical atomic physics groups studying laser cooling, optical frequency standards, cold collisions, and quantum degenerate gases. This experimental research program focuses on determining collisional properties and ground state potentials that will form the foundation for continued progress in the application of strontium, such as scattering lengths for optimizing evaporative cooling or collisional clock shifts, or long range potential parameters to compare with atomic structure calculations. The first experiments will be two-color photoassociative spectroscopy of the highest-lying levels of the diatomic strontium molecular ground-state potential. Later experiments will take advantage of the information learned to explore optically induced Feshbach resonances and create quantum degenerate gases. Strontium Bose-Einstein condensation will not simply demonstrate another condensed atom. Optically induced Feshbach resonances will allow flexible manipulation of atom-atom interactions on a more rapid time scale or finer spatial scale than is possible with magnetic Feshbach resonances. The lack of hyperfine structure in bosonic isotopes may make condensates insensitive to environmental perturbations and better suited for atom-optic and interferometric applications. The broader impact of the program involves education of students as well as efforts in diversity.