PM: Cavity-based Atomic Gravimeter

PM：腔体原子重力计

• 批准号: 2208029
• 负责人: Holger Mueller
• 金额: $ 118.01万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2027-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2208029&HistoricalAwards=false
• 关键词: PM; Cavity; based; Atomic; Gravimeter

Applying the principles of quantum mechanics holds promise to make extremely precise measurements, beyond the capabilities of more traditional methods. However, unwanted interactions of the quantum measurement device with the environment negate the advantages of quantum measurement in a process known as decoherence. One particularly interesting class of quantum measurement devices are atom interferometers. To avoid unwanted decoherence, they are usually performed with particles in free fall, but the available height limits these setups to time scales below 3 seconds. This project builds on an alternative approach, suspending atoms in a laser beam that forms a periodic, attractive potential for the atoms. The aim is to realize coherences for as long as several minutes, and thereby realize the most sensitive atomic device to measure gravity. This will then be applied to fundamental research in gravitational physics. In addition, the research will have broader impacts in contributing to UC Berkeley's efforts to educate a "quantum workforce" by offering hands-on training to undergraduate and graduate students.The proposal builds on the previous demonstration of 20-second coherences in a lattice-hold atom interferometer using an optical lattice formed by a resonant laser beam inside an optical resonator. Based on the observation that lowering the atom temperatures strongly increases the coherence, longer coherence times will be achieved by upgrading the experiment with a Bose-Einstein condensed (BEC) atomic sample. The next step will be to test whether the strongly reduced atomic temperature will lead to minutes of coherence time and a sensitivity of up to 2 nano-g in one second of integration time (where g is the earth's acceleration of free fall), realizing the world’s most sensitive atomic gravimeter. If this is successful, it will form the basis for the proposed test of the gravitational Aharonov-Bohm effect, in which a miniaturized test mass will form a "w"-shaped gravitational potential. Atomic wave packets will be brought to two points at which the potential does not apply forces on the atoms, and the Aharonov-Bohm induced phase shift will be recorded.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.

应用量子力学的原理有望进行非常精确的测量，超越传统方法的能力。然而，量子测量设备与环境的不必要的相互作用在称为退相干的过程中否定了量子测量的优点。一种特别有趣的量子测量设备是原子干涉仪。为了避免不必要的退相干，它们通常是在自由落体的颗粒上进行的，但是可用的高度将这些设置限制在3秒以下的时间尺度。该项目建立在另一种方法的基础上，将原子悬浮在激光束中，形成原子的周期性吸引力。其目标是实现长达数分钟的相干，从而实现最灵敏的原子装置来测量重力。这将应用于引力物理学的基础研究。此外，该研究还将对加州大学伯克利分校培养“量子劳动力”的努力产生更广泛的影响，为本科生和研究生提供实践培训。该提案建立在之前使用光学谐振器内的谐振激光束形成的光学晶格在晶格保持原子干涉仪中进行20秒相干的演示的基础上。基于降低原子温度强烈增加相干性的观察，通过用玻色-爱因斯坦凝聚（BEC）原子样品升级实验将实现更长的相干时间。下一步将是测试强烈降低的原子温度是否会导致几分钟的相干时间和一秒积分时间内高达2毫微微克的灵敏度（其中g是地球自由落体的加速度），实现世界上最灵敏的原子重力仪。如果这是成功的，它将成为拟议的阿哈罗诺夫-玻姆效应测试的基础，其中一个小型化的测试质量将形成一个“w”形的引力势。原子波包将被带到两个点，在这两个点上，电势不会对原子施加力，Aharonov-Bohm引起的相移将被记录下来。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Atomic gravimeter robust to environmental effects

• DOI: 10.1063/5.0163101
• 发表时间: 2023-08-07
• 期刊: APPLIED PHYSICS LETTERS
• 影响因子: 4
• 作者: Panda，Cristian D. D.;Tao，Matt;Muller，Holger
• 通讯作者: Muller，Holger