Probing gravity by holding atoms for 20 seconds
Probing gravity by holding atoms for 20 seconds
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DOI：
10.1126/science.aay6428
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发表时间：
2019-07
期刊：
影响因子：
56.9
通讯作者：
V. Xu;Matt Jaffe;C. Panda;Sofus L. Kristensen;Logan W. Clark;H. Müller
中科院分区：
文献类型：
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作者：
V. Xu;Matt Jaffe;C. Panda;Sofus L. Kristensen;Logan W. Clark;H. Müller
在干涉仪装置中利用原子的波动性质可以用来提供对重力的精确测量。精度受限于干涉测量的时间尺度，而时间尺度又受限于原子下落的距离，对于10米的下落塔来说，通常仅超过几秒。Xu等人描述了一种捕获原子干涉仪，其中干涉测量的询问时间可以延长到20秒。新的干涉仪设计和随后改进的精度可以用来进行广义相对论的基本测试以及其他潜在的精确测量。科学，本期第745页，将被困原子在干涉仪中长达20秒，提供了一种灵敏的引力测量方法。原子干涉仪是基础物理测量和惯性传感应用的有力工具。然而，它们的性能受到引力场中自由下落原子的可用询问时间的限制。通过将空间分离的原子波包悬浮在由光腔模式形成的晶格中，我们实现了20秒的询问时间。我们的方法允许通过保持而不是下降原子来测量引力势。经过数秒的保持时间，重力势能差从微米的垂直分离产生兆弧度的干涉仪相位。这种被困的几何形状抑制了由于振动的相位变化由三到四个数量级，克服了原子干涉重力仪的主要噪声源。
Trapped atoms to probe gravity Exploiting the wave nature of atoms in an interferometer setup can be used to provide a precise measure of gravity. The precision is limited to the time scale of the interferometric measurement, which in turn is limited to the distance that the atoms drop, typically just over a couple of seconds for a 10-meter drop tower. Xu et al. describe a trapped atom interferometer in which the interrogation time of the interferometric measurements can be extended to 20 seconds. The new interferometer design and subsequent improved precision can be used to make fundamental tests of general relativity as well as precision measurements of other potentials. Science, this issue p. 745 Holding trapped atoms in an interferometer for up to 20 seconds provides a sensitive measure of gravity. Atom interferometers are powerful tools for both measurements in fundamental physics and inertial sensing applications. Their performance, however, has been limited by the available interrogation time of freely falling atoms in a gravitational field. By suspending the spatially separated atomic wave packets in a lattice formed by the mode of an optical cavity, we realize an interrogation time of 20 seconds. Our approach allows gravitational potentials to be measured by holding, rather than dropping, atoms. After seconds of hold time, gravitational potential energy differences from as little as micrometers of vertical separation generate megaradians of interferometer phase. This trapped geometry suppresses the phase variance due to vibrations by three to four orders of magnitude, overcoming the dominant noise source in atom-interferometric gravimeters.