@article{13618,
  author = {Kyungtae Kim and Alexander Aeppli and William Warfield and Anjun Chu and Ana Rey and Jun Ye},
  title = {Atomic Coherence of 2 Minutes and Instability of 1.5 x 10^-18 at 1 s in a Wannier-Stark Lattice Clock},
  abstract = {<p>We explore the limits of atomic coherence and measurement precision in a 87Sr optical lattice clock. We<br>perform a detailed characterization of key effects, including lattice Raman scattering and atomic collisions<br>in a shallow lattice configuration, determining a 174(28) s 3P0 clock state lifetime. Investigation of atomic<br>coherence across a range of lattice depths and atomic densities reveals decoherence mechanisms related to<br>photon scattering and atomic interaction. At a reduced density, we observe a coherence time of 118(9) s,<br>approaching the fundamental limit set by spontaneous emission. Guided by this coherence understanding,<br>we demonstrate a clock instability for an atomic ensemble of 1.5 × 10<sup>−18</sup> at 1 s in fractional frequency<br>units. Our results are important for further advancing the state of the art of an optical lattice clock for<br>fundamental physics applications.</p>},
  year = {2025},
  journal = {Physical Review Letters},
  volume = {135},
  pages = {103601},
  month = {2025-07},
  publisher = {American Physical Society},
  url = {https://link.aps.org/doi/10.1103/3wtv-sty2},
  doi = {10.1103/3wtv-sty2},
}