Precision measurements using atoms and molecules

人类观察天空已经有几个世纪了，但整个宇宙的现象对我们的电磁眼和望远镜来说是不可见的。宇宙中的每一个大质量物体都辐射引力波，它可以从宇宙的遥远角落向我们传递信息。然而，这个引力宇宙仍然隐藏在视野之外，等待着足够精确的仪器的发展，以探测引力波引起的微弱时空波动。拟议的研究计划旨在构建精确的原子工具，以开发引力波望远镜和其他精密仪器。 原子和分子是我们可以利用的最精确的物理工具。它们的量子态可以被精细地控制，这使得它们可以被用作具有极其规则频率的振荡器-这种原子频率参考是电磁“音叉”。正如一套不起眼的音叉对于演奏复杂的管弦乐至关重要一样，电磁频率基准对于许多现代技术任务的执行至关重要，包括通信，无线电测距和导航。这些稳定的振子提供了一组均匀间隔的滴答声，也可以用来测量由引力波引起的时空扭曲。我们的研究计划旨在构建新的频率基准，是强大的和便携式的，并可用作精密仪器的积木。该研究计划中开发的频率参考将提供光学和太赫兹频率的稳定标记，可用于改进时间保持，精确卫星测距和下一代通信技术。该研究计划将培养本科生，研究生和博士后在高科技行业的领导地位，在那里他们将能够利用他们的经验与精密测量。 为了用引力观测宇宙中最遥远的物体，需要更精确的原子频率参考。提高精度的途径是通过使用量子纠缠，其中数千个原子的整个系综可以表现为一个相关的量子系统。使用这种纠缠系综可以提高测量精度，而不会产生单个原子和分子不相关波动所产生的噪声。我们的长期目标是研究使用量子纠缠来构建具有增强性能的原子和分子频率参考。这也将开辟使用原子和分子对量子电动力学等基本物理理论进行严格测试的方法，探测这些理论结构中的裂缝，这将标志着新的未知物理学的开始。

Humankind has observed the sky for centuries, but an entire universe of phenomena is invisible to our electromagnetic eyes and telescopes. Every massive object in the universe radiates gravitational waves, which can carry information to us from the far corners of the universe. Yet, this gravitational universe remains hidden from view, and awaits the development of instruments precise enough to detect the feeble spacetime fluctuations caused by gravitational waves. The proposed research program aims to construct precise atomic tools to enable the development of gravitational wave telescopes and other precision instruments. Atoms and molecules are the most precise physical tools available to us. Their quantum states can be exquisitely controlled, which allows them to be used as oscillators with extremely regular frequencies - such atomic frequency references are electromagnetic “tuning forks”. Just as a humble set of tuning forks is vital to the performance of a complex orchestral symphony, electromagnetic frequency references are essential for the performance of many modern technological tasks, including communication, radio ranging and navigation. These stable oscillators provide sets of evenly spaced ticks, which can also be used to measure the distortions of spacetime caused by passing gravitational waves. Our research program aims to construct novel frequency references that are robust and portable, and can be used as the building blocks of precision instruments. The frequency references developed in this research program will provide stable markers at optical and terahertz frequencies, which can be used for improved time-keeping, accurate satellite ranging, and in the next generation of communications technologies. The research program will train undergraduates, graduate students, and postdocs for leadership positions in the high-technology industry, where they will be able to leverage their experience with precision measurements. To gravitationally observe the most distant objects in the universe, ever more precise atomic frequency references are needed. The path to improved precision is through the use of quantum entanglement, where an entire ensemble of thousands of atoms can behave as one correlated quantum system. Measurements with improved precision can be made using such entangled ensembles, without the noise that arises from uncorrelated fluctuations of individual atoms and molecules. Our long-term goal is to investigate the use of quantum entanglement to build atomic and molecular frequency references with enhanced performance. This will also open up ways to use atoms and molecules for stringent tests of fundamental physical theories such as quantum electrodynamics, probing for cracks in the structure of these theories that would signal the onset of new and unknown physics.