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Observation and Absolute Frequency Measurements of the 1S0 - 3P0 Optical Clock Transition in Neutral Ytterbium



C Hoyt, Zeb Barber, Christopher W. Oates, Scott A. Diddams, Tara M. Fortier, Leo W. Hollberg


We report the direct excitation of the highly forbidden (6s2) 1S0 - (6s6p) 3P0 optical transition in two odd isotopes of ytterbium. As the excitation laser frequency is scanned, absorption is seen by monitoring the depletion from an atomic cloud at ~70 microK in a magneto-optical trap. The F=1/2 - F=1/2 frequency in 171Yb is 518,295,836,608.5 (1.5) kHz. The F=5/2 - F=5/2 frequency in 173Yb is 518,294,576,858.6 (5.0) kHz. Made with a femtosecond-laser frequency comb calibrated by the NIST cesium fountain clock, these measurements represent over a million-fold reduction in uncertainty. The natural linewidth of these J=0 to J=0 transitions is calculated to be ~10 mHz, making them well-suited to support a new generation of optical atomic clocks based on confinement in an optical lattice.
Physical Review Letters


atomic spectroscopy, optical cooling and trapping of atoms, spectroscopic techniques, time and frequency


Hoyt, C. , Barber, Z. , Oates, C. , Diddams, S. , Fortier, T. and Hollberg, L. (2005), Observation and Absolute Frequency Measurements of the <sup>1</sup>S<sub>0</sub> - <sup>3</sup>P<sub>0</sub> Optical Clock Transition in Neutral Ytterbium, Physical Review Letters, [online], (Accessed June 16, 2024)


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Created August 19, 2005, Updated February 17, 2017