Resolving the gravitational redshift across a millimetre-scale atomic sample
Resolving the gravitational redshift across a millimetre-scale atomic sample
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DOI：
10.1038/s41586-021-04349-7
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发表时间：
2022-02-17
期刊：
影响因子：
64.8
通讯作者：
Ye, Jun
中科院分区：
文献类型：
--
作者：
Bothwell, Tobias;Kennedy, Colin J.;Ye, Jun
爱因斯坦的广义相对论指出，相对于实验室坐标，不同的引力势棒以不同的速率进行计时，这种效应称为引力红移(1)。作为空间和时间的基本探测器，原子钟长期以来一直在 30 厘米到数千公里的距离范围内测试这一预测(2-4)。最终，一旦时钟对弯曲时空中振荡的量子物体的有限波函数变得敏感，它们将使广义相对论和量子力学的联合研究成为可能。针对这种情况，我们测量了与超冷锶的单个毫米级样品内的引力红移一致的线性频率梯度。我们的结果是通过将分数频率测量不确定度提高了 10 倍以上，现在达到 7.6 x 10(-21) 来实现的。这预示着一种新的时钟运行机制，需要对引力扰动进行样本内校正。
Einstein's theory of general relativity states that clocks at different gravitational potentialstick at different rates relative to lab coordinates-an effect known as the gravitational redshift(1). As fundamental probes of space and time, atomic clocks have long served to test this prediction at distance scales from 30 centimetres to thousands of kilometres(2-4) . Ultimately, clocks will enable the study of the union of general relativity and quantum mechanics once they become sensitive to the finite wave function of quantum objects oscillating in curved space-time. Towards this regime, we measure a linear frequency gradient consistent with the gravitational redshift within a single millimetre-scale sample of ultracold strontium. Our result is enabled by improving the fractional frequency measurement uncertainty by more than a factor of 10, now reaching 7.6 x 10(-21). This heralds a new regime of clock operation necessitating intra-sample corrections for gravitational perturbations.