Excited-Band Coherent Delocalization for Improved Optical Lattice Clock Performance

• Published in: Physical review letters Vol. 132; no. 13; p. 133201
• Main Authors: Siegel, J L, McGrew, W F, Hassan, Y S, Chen, C-C, Beloy, K, Grogan, T, Zhang, X, Ludlow, A D
• Format: Journal Article
• Language: English
• Published: United States 29.03.2024
• ISSN: 1079-7114
• DOI: 10.1103/PhysRevLett.132.133201

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 coherent delocalization, we suppress cold-collision shifts and two-body losses. Atom loss attributed to Landau-Zener tunneling in the ground lattice band would compromise coherent delocalization at low trap depths for our ^{171}Yb 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 ^{3}P_{0} excited state as 5.7(7)×10^{-4}  E_{r}^{-1} s^{-1} and 19(2) s, respectively.