Kobayashi J, Ogino A, Inouye S
Department of Physics, Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan.
PRESTO, Japan Science and Technology Agency, Kyoto, 606-8502, Japan.
Nat Commun. 2019 Aug 21;10(1):3771. doi: 10.1038/s41467-019-11761-1.
Experimental techniques to manipulate cold molecules have seen great development in recent years. The precision measurements of cold molecules are expected to give insights into fundamental physics. Here we use a rovibrationally pure sample of ultracold KRb molecules to improve the measurement on the stability of electron-to-proton mass ratio [Formula: see text]. The measurement is based upon a large sensitivity coefficient of the molecular spectroscopy, which utilizes a transition between a nearly degenerate pair of vibrational levels each associated with a different electronic potential. Observed limit on temporal variation of μ is [Formula: see text], which is better by a factor of five compared with the most stringent laboratory molecular limits to date. Further improvements should be straightforward, because our measurement was only limited by statistical errors.
近年来，用于操控冷分子的实验技术取得了巨大发展。冷分子的精确测量有望为基础物理学提供深刻见解。在此，我们使用超冷KRb分子的振转纯样品来改进对电子与质子质量比稳定性的测量[公式：见原文]。该测量基于分子光谱的高灵敏度系数，利用了一对近乎简并的振动能级之间的跃迁，每个能级与不同的电子势能相关。观测到的μ随时间变化的极限为[公式：见原文]，与迄今为止最严格的实验室分子极限相比，提高了五倍。进一步的改进应该很简单，因为我们的测量仅受统计误差限制。
