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Search Publications by: Willa Dworschack (Assoc)

Displaying 1 - 2 of 2

Optical clock frequency ratios with uncertainty ? 3.2 * 10^-18

January 6, 2026

Author(s)

Alexander Aeppli, Willa Arthur-Dworschack, Kyle Beloy, Caitlin Berry, Tobias Bothwell, Angela Folz, Tara Fortier, Tanner Grogan, Youssef Hassan, Zoey Zimeng Hu, David Hume, Benjamin Hunt, Kyungtae Kim, Amanda Koepke, Dahyeon Lee, David Ray Leibrandt, Ben Lewis, Andrew Ludlow, Mason Marshall, Nicholas Nardelli, Harikesh Ranganath, Daniel Rodriguez Castillo, Jeffrey Sherman, Jacob Siegel, Suzanne Thornton, William Warfield, Jun Ye

We report high-precision frequency ratio measurements between optical atomic clocks based on 27Al+, 171Yb, and 87Sr. With total fractional uncertainties at or below 3.2 × 10−18, these measurements meet the milestone criteria for redefinition of the second

High-Stability Single-Ion Clock with 5.5 x 10^-19 Systematic Uncertainty

July 14, 2025

Author(s)

Mason Marshall, Daniel Rodriguez Castillo, Willa Dworschack, Alexander Aeppli, Kyungtae Kim, Dahyeon Lee, William Warfield, Nicholas Nardelli, Tara Fortier, Jun Ye, David Ray Leibrandt, David Hume

We report a single-ion optical atomic clock with fractional frequency uncertainty of 5.5 x 10^-19 and frequency stability of 3.5 x 10^-16/sqrttau/s}, based on quantum logic spectroscopy of a single 27Al+ ion. A co-trapped 25Mg+ ion provides sympathetic

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