Improved frequency ratio measurement with 87Sr and 171Yb optical lattice clocks at NMIJ. (7th January 2021)

• Record Type: Journal Article
• Authors: Hisai, Yusuke; Akamatsu, Daisuke; Kobayashi, Takumi; Hosaka, Kazumoto; Inaba, Hajime; Hong, Feng-Lei; Yasuda, Masami
• Is Part Of: Metrologia. Volume 58:Number 1(2021)
• Publication Date: 2021-01-07
• Subjects: optical lattice clock -- frequency metrology -- frequency ratio -- frequency measurement -- SI second; Weights and measures -- Periodicals; Weights and Measures -- Periodicals; 530.805
• DOI: 10.1088/1681-7575/abc104
• Languages: English
• ISSNs: 0026-1394

Abstract

Abstract: We report improved frequency ratio measurement with 87 Sr and 171 Yb optical lattice clocks at the National Metrology Institute of Japan. The 87 Sr optical lattice clock is enhanced with several major modifications and is re-evaluated with a reduced uncertainty of 1.1 × 10 −16 . We employed a 171 Yb optical lattice clock with an uncertainty of 4 × 10 −16 that was developed for contributing to International Atomic Time. The measurement result is ν Yb / ν Sr = 1.207 507 039 343 338 58(49)sys (6)stat with a fractional uncertainty of 4.1 × 10 −16, which is 3.4 times smaller than our previous measurement result.