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Direct Excitation of the Forbidden Clock Transition in Neutral 174Yb Atoms Confined to an Optical Lattice



Zeb Barber, C Hoyt, Christopher W. Oates, Leo W. Hollberg, A. V. Taichenachev, V. I. Yudin


We report direct single laser excitation of the strictly forbidden (6s2)1S0 –(6s6p)3P0 clock transition in the even 174Yb isotope confined to a 1-D optical lattice. A small (~1.2mT) static magnetic field is used to induce a non-zero electric dipole transition probability between the clock states at the ground-to-excited state splitting of 578.42nm. Ultra-narrow resonance linewidths of 20Hz (FHWM) with high contrast were observed. The previously unknown ac Stark shift-canceling (magic) wavelength is determined to be 759.35 ± 0.02 nm. The method can be easily implemented in current Yb and Sr optical lattice clock experiments to extend their studies to the metrologically preferred even isotopes. Furthermore, this magnetic field-induced spectroscopic method can be employed with the even isotopes of other alkaline earth-like atoms (e.g. Mg, Ca), creating new clock possibilities.
Physical Review Letters


neutral atoms, optical frequency standards, optical lattice clock, precision spectroscopy, Yb, ytterbium


Barber, Z. , Hoyt, C. , Oates, C. , Hollberg, L. , Taichenachev, A. and Yudin, V. (2006), Direct Excitation of the Forbidden Clock Transition in Neutral <sup>174</sup>Yb Atoms Confined to an Optical Lattice, Physical Review Letters, [online], (Accessed April 18, 2024)
Created March 3, 2006, Updated February 19, 2017