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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.

Physical Review Letters
|October 2, 2009
PubMed
Summary
This summary is machine-generated.

Researchers developed a highly precise ytterbium-171 optical lattice clock. This atomic clock achieved a fractional uncertainty of 3.4 x 10^-16, advancing timekeeping accuracy.

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Area of Science:

  • Atomic Physics
  • Metrology
  • Quantum Optics

Background:

  • Optical atomic clocks offer superior precision over traditional microwave clocks.
  • Ytterbium-171 is a promising candidate for optical clocks due to its suitable atomic structure.
  • Accurate frequency measurements are crucial for fundamental physics and technological applications.

Purpose of the Study:

  • To experimentally investigate and characterize an optical clock based on ytterbium-171 atoms.
  • To evaluate and minimize frequency shifts affecting clock accuracy.
  • To establish the absolute frequency of the clock transition with high precision.

Main Methods:

  • Confining ytterbium-171 atoms in an optical lattice.
  • Evaluating various frequency shifts, including density-dependent collision and blackbody radiation Stark shifts.
  • Measuring the absolute clock transition frequency against a primary cesium fountain clock (NIST-F1).

Main Results:

  • Achieved a fractional uncertainty of 3.4 x 10^-16 for the optical clock.
  • Identified uncertainty in the blackbody radiation Stark shift as the primary limitation.
  • Measured the absolute clock transition frequency as 518 295 836 590 865.2(0.7) Hz.

Conclusions:

  • The ytterbium-171 optical lattice clock demonstrates state-of-the-art performance.
  • Further improvements require reducing uncertainty in the blackbody radiation Stark shift.
  • The measured frequency provides a precise benchmark for atomic timekeeping.