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Excited-Band Coherent Delocalization for Improved Optical Lattice Clock Performance



Jacob Siegel, Andrew Ludlow, Youssef Hassan, Kyle Beloy, Tanner Grogan, Chun-Chia Chen


We implement coherent delocalization as a tool for improving the two primary metrics of atomic clock performance: systematic uncertainty and instability. By decreasing atomic density with co- herent delocalization, we suppress cold-collision shifts and two-body losses. Atom loss attributed to Landau-Zener tunneling would otherwise compromise coherent delocalization at low trap depths for our 171Yb atoms; hence, we implement for the first time delocalization in excited lattice bands. Doing so increases the spatial distribution of atoms trapped in the vertically-oriented optical lattice by ∼ 7 times. At the same time we observe a reduction of the cold-collision shift by 6.5(8) times, while also making inelastic two-body loss negligible. With these advantages, we measure the trap- light-induced quenching rate and natural lifetime of the 3P0 excited-state as 5.7(7) × 10−4 Er −1s−1 and 19(2) s, respectively.
Physical Review Letters


Siegel, J. , Ludlow, A. , Hassan, Y. , Beloy, K. , Grogan, T. and Chen, C. (2024), Excited-Band Coherent Delocalization for Improved Optical Lattice Clock Performance, Physical Review Letters, [online],, (Accessed June 25, 2024)


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Created March 24, 2024, Updated June 7, 2024