RUI: PM: Optical Molecular Clocks for New Physics Searches

RUI：PM：用于新物理搜索的光学分子钟

• 批准号: 2207623
• 负责人: David Hanneke
• 金额: $ 56.11万
• 依托单位: Amherst College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-15 至 2025-06-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2207623&HistoricalAwards=false
• 关键词: RUI; PM; Optical; Molecular; Clocks

Some atoms and molecules possess quantum states with properties that are particularly well-suited to use in timekeeping, quantum information, or tests of physical laws. This award focuses on molecular vibrations – where the atomic nuclei stretch and compress the chemical bond. The project will demonstrate the tools needed to use molecular vibrations as precise frequency references (that is as good clocks) and is a stepping stone on the way towards searching for changes in the basic physical parameters of nature (such as how many times heavier the proton is than the electron). Such changes are predicted by some models of quantum gravity or dark matter, but none have yet been observed in the lab. This research takes place at a liberal arts college, and undergraduate students are involved in all aspects of the work. The project will advance the career of a postdoctoral scholar. In addition to training the next generation of scientists, this work develops skills in experimental physics that are transferable to a wide array of future endeavors.This award enables investigation of laser-driven vibrational transitions in molecular ions. The particular transition here – from the ground vibrational state to a vibrationally excited state in the diatomic oxygen molecular cation – has a narrow natural linewidth, high sensitivity to changing fundamental constants, and long-term prospects as an optical molecular clock. The nonpolar nature of the molecule suppresses systematic shifts related to electric fields, such as AC Stark shifts and blackbody radiation. Molecular vibrations hold great promise for next-generation searches for drifts or oscillations in the proton-to-electron mass ratio. This project builds on the PI’s experience with trapped charged particles as well as existing infrastructure for producing quantum-state-selected molecular ions. These ions will be loaded into a trap and sympathetically cooled with co-trapped atomic ions. The trapping enables long probe times, which will be needed to precisely determine the transition frequency and to demonstrate a proof-of-principle search for variation in the proton-to-electron mass ratio. Such a search is a probe of additional dimensions, new scalar fields, and ultralight dark matter.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.

一些原子和分子潜在的量子状态具有特性，特别适合用于计时，量子信息或物理定律测试。该奖项的重点是分子振动 - 原子核拉伸并压缩化学键。该项目将展示使用分子振动作为精确频率参考（即好时钟）所需的工具，并且是寻找自然基本物理参数变化的途径（例如质子比电子的重量比电子更重）。某些量子重力或暗物质模型预测了这种变化，但在实验室中尚未观察到。这项研究是在一所文科学院进行的，本科生参与了工作的各个方面。该项目将推进博士后科学的职业。除了培训下一代科学家外，这项工作发展的实验物理学技能将转移到许多未来的努力中。该奖项使分子离子中激光驱动的振动过渡的投资。这里的特定过渡 - 从地面振动状态到双原子氧分子阳离子中几乎激发的状态 - 具有狭窄的自然线宽，对变化基本常数的敏感性高以及长期前景作为光学分子钟。该分子的非极性性质抑制了与电场相关的系统变化，例如AC Stark Shift和Blackbody辐射。分子振动对于下一代搜索质子与电子质量比的钻或振荡有很大的希望。该项目基于PI在被困的带电颗粒以及用于产生量子态培养的分子离子的现有基础设施的基础上。这些离子将被加载到陷阱中，并用共捕获的原子离子对称冷却。该捕获可以实现较长的探测时间，这将需要精确确定过渡频率并证明原则上的搜索验证质子与电子质量比的变化。这种搜索是对其他维度，新标量领域和超轻暗物质的调查。该奖项反映了NSF的法定任务，并使用基金会的知识分子优点和更广泛的影响审查标准，认为通过评估被认为是珍贵的支持。