NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
p-Wave Cold Collisions in an Optical Lattice Clock
Published
Author(s)
Nathan D. Lemke, Andrew D. Ludlow, J. von Stecher, Jeffrey A. Sherman, A.M. Rey, Christopher W. Oates
Abstract
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.
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 October 10, 2025)