RUI: Search for a spin-gravity coupling using laser-addressed atomic gyroscopes

RUI：使用激光寻址原子陀螺仪寻找自旋重力耦合

• 批准号: 0652824
• 负责人: Derek Kimball
• 金额: $ 25.42万
• 依托单位: California State University, East Bay Foundation, Inc.
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-07-01 至 2010-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0652824&HistoricalAwards=false
• 关键词: RUI; Search; spin; gravity; coupling

This award supports an experiment to search for a new long-range coupling between nuclear spins and the mass of the Earth. Depending on interpretation, the experiment would improve present experimental limits by as much as two orders of magnitude or more. The presence of such an interaction would imply the existence of a gravitational dipole moment (GDM) of an elementary particle --- which can be envisioned semiclassically as a small separation between the position of the center of inertial mass and the center of gravitational mass. Detection of a GDM would be evidence that gravity violated parity and time-reversal symmetries to a small degree, as well as being a breakdown of the equivalence principle which underlies the theory of general relativity. The experiment would also set new experimental limits on hypothetical scalar and vector components of gravitational fields, and new limits on the existence of certain classes of massless or nearly massless axion-like pseudoscalar particles. This new experimental search is motivated by recently developed techniques in the field of atomic magnetometry enabling significant improvement in sensitivity to atomic spin precession. The experiment will use nonlinear optical rotation of near-resonant laser light to measure the spin-precession frequency of alkali atoms in the presence of a magnetic field and use differences between the frequencies for the two different ground state hyperfine levels to search for a signal proportional only to anomalous interactions.This work will fundamentally advance our knowledge of the gravitational force by testing how well gravity respects parity and time-reversal symmetries, and by probing the limits of the equivalence principle. Tremendous efforts at the theoretical level are being undertaken to integrate our understanding of gravity into the framework of quantum field theory, and this work offers a unique opportunity to gain new experimental insight into the symmetry properties of gravity. Furthermore, new techniques for precision measurement of the precession of spin-polarized atoms will be developed, advancing the technology driving the next generation of ultra-sensitive atomic magnetometers and gyroscopes.This research program forms the basis for an integrative approach to hands- on education in experimental physics at California State University, East Bay. New curricula for the advanced laboratory course will be developed to provide a natural connection to the ongoing research, and undergraduate students will be directly involved in the research program. An active research program at this institution will especially benefit a diverse student population, since two-thirds of our students are women and over seventy percent are underrepresented minorities.

该奖项支持一个实验，以搜索核自旋与地球质量之间的新远程耦合。根据解释，实验将把当前的实验限制提高到多达两个数量级或更多。这种相互作用的存在意味着基本粒子的重力偶极矩（GDM）的存在 - 可以半经典地设想为惯性质量中心的位置与重力质量中心之间的小分离。 GDM的检测将证明重力在很小的程度上违反了平等和时间反转的对称性，并且是对等价原理的分解，而对等原理是基于一般相对论的理论。该实验还将对重力场的假设标量和矢量成分设定新的实验限制，并将某些类别的无质量或几乎无质量的轴突样假单胞菌颗粒存在新的限制。这种新的实验搜索是由最近在原子磁力测定领域开发的技术激励的，从而可以显着提高对原子自旋进动的敏感性。该实验将利用近谐振激光光的非线性光学旋转来测量在存在磁场的情况下碱原子的自旋频率频率，并在两个不同的基态超细水平上使用频率之间的差异，以仅搜索信号与异常相互作用，从根本上依赖于我们的良好范围。并通过探测等价原理的限制。正在为将我们对重力的理解纳入量子场理论框架的巨大努力，这项工作提供了一个独特的机会，以获得对重力对称性的新实验性见解。此外，将开发用于精确测量自旋原子进动的新技术，促进推动下一代超敏感的原子磁力计和陀螺仪的技术。这项研究计划构成了综合方法的基础 - 在东湾加利福尼亚州立大学实验性物理学方面的教育方法。将开发有关高级实验室课程的新课程，以提供与正在进行的研究的自然联系，并且本科生将直接参与研究计划。该机构的一项积极研究计划将特别受益于不同的学生人口，因为我们三分之二的学生是妇女，而超过70％的学生人数不足。