A 1D Strontium Optical Lattice Clock With Record Low Intrinsic Instability

Amongst atomic references under development for the redefinition of the second, strontium  has demonstrated several important scientific results,  including record instability [1], record atom-atom coherence times [2], and near record accuracy [3]. Our newly upgraded 1D strontium optical lattice clock is currently being evaluated to push the frontiers of all three. Here we report on record low instability and atom-atom coherence time comparable with recent demonstrations. We utilize self-synchronous imaging to rapidly measure intra-cloud frequency differences, a critical step towards ensuring frequency homogeneity across atomic samples necessary for accuracy at the 19th digit.

[1] Oelker, E., et al. "Demonstration of 4.8×10^-17 stability at 1 s for two independent optical clocks." Nature Photonics 13.10 (2019): 714-719.

[2] Young, Aaron W., et al. "Half-minute-scale atomic coherence and high relative stability in a tweezer clock." Nature 588.7838 (2020): 408-413.

[3] Bothwell, Tobias, et al. "JILA SrI optical lattice clock with uncertainty of 2.0×10^-18." Metrologia 56.6 (2019): 065004.