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p-Wave Cold Collisions in an Optical Lattice Clock



Nathan D. Lemke, Andrew D. Ludlow, J. von Stecher, Jeffrey A. Sherman, A.M. Rey, Christopher W. Oates


State-of-the-art optical clocks with neutral atoms employ an optical lattice to tightly confine the atoms, enabling high-resolution spectroscopy and the potential for high-accuracy timekeeping. Interrogating many atoms simultaneously facilitates high measurement precision, but also yields high atomic density and the potential for cold collisions. To suppress these atom-atom interactions, the use of ultracold, spin-polarized fermions was proposed to exploit the Fermi suppression of s-wave collisions while freezing out higher-wave contributions. However, small collision shifts have been measured in Sr and Yb. For Sr, the shifts were attributed to s-wave interactions enabled by excitation inhomogeneity. Here, we report definitive experimental evidence and a quantitative theoretical treatment of p-wave collisions in Yb. We also demonstrate a novel suppression of the collisional frequency shift utilizing strong interactions in a two-dimensional optical lattice. Understanding these interactions and dynamics for two-valence-electron atoms is fundamental for the development of quantum information and computation protocols and simulation of condensed matter many-body Hamiltonians.
Nature Physics


Lasers, spectroscopy


Lemke, N. , Ludlow, A. , von, J. , Sherman, J. , Rey, A. and Oates, C. (2011), p-Wave Cold Collisions in an Optical Lattice Clock, Nature Physics (Accessed September 25, 2023)
Created September 2, 2011, Updated February 19, 2017