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Updated: Jun 19, 2026

Fabrication and Testing of Microfluidic Optomechanical Oscillators
Published on: May 29, 2014
Spin-1/2 optical lattice clock
N D Lemke1, A D Ludlow, Z W Barber
1National Institute of Standards and Technology, Boulder, Colorado 80305, USA.
Abstract:
We experimentally investigate an optical clock based on ;{171}Yb (I = 1/2) atoms confined in an optical lattice. We have evaluated all known frequency shifts to the clock transition, including a density-dependent collision shift, with a fractional uncertainty of 3.4 x 10;{-16}, limited principally by uncertainty in the blackbody radiation Stark shift. We measured the absolute clock transition frequency relative to the NIST-F1 Cs fountain clock and find the frequency to be 518 295 836 590 865.2(0.7) Hz.
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