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Measurement of the variation of electron-to-proton mass ratio using ultracold molecules produced from laser-cooled atoms.

ABSTRACT: 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 ? 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.

SUBMITTER: Kobayashi J

PROVIDER: S-EPMC6704166 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Measurement of the variation of electron-to-proton mass ratio using ultracold molecules produced from laser-cooled atoms.

Kobayashi J J Ogino A A Inouye S S

Nature communications 20190821 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 nea ...[more]

PMID: 31434889

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