Ytterbium optical lattice clock with instability of order 10-18

作者：Zhang, Ang; Xiong, Zhuanxian; Chen, Xiaotong; Jiang, Yanyi^*; Wang, Jinqi; Tian, Congcong; Zhu, Qiang; Wang, Bing; Xiong, Dezhi; He, Lingxiang; Ma, Longsheng; Lyu, Baolong^*

来源：Metrologia, 2022, 59(6): 065009.

DOI：10.1088/1681-7575/ac99e4

• optical lattice clock
• ytterbium atoms
• Rabi spectroscopy
• frequency instability

We have built an ytterbium optical lattice clock with improvements over our previous version. An in-vacuum blackbody radiation (BBR) shield is employed to provide a well characterized BBR environment. The effective temperature felt by the atoms can be determined at an accuracy level of 13 mK, leading to a total BBR frequency shift uncertainty of 9.5 x 10(-19). We have also built an ultra-stable optical cavity system to pre-stabilize the clock laser, achieving a flicker frequency instability of similar to 3 x 10(-16). Rabi spectroscopy of the lattice-trapped atoms can achieve sub-Hertz linewidth spectra. Two ytterbium clocks have been operated in an antisynchronized configuration, with real-time BBR-Stark-shift corrections applied to both of them. By comparing the two clocks, we demonstrate a single-clock instability of 5.4 x 10(-18) in 4500 s. This clock will be applied for frequency comparisons to other optical clocks of different atomic species in the future.

• 单位
  中国科学院研究生院