Testing the stability of fundamental constants with the 199Hg+ single-ion optical clock

S. Bize; S. A. Diddams; U. Tanaka; C. E. Tanner; W. H. Oskay; R. E. Drullinger; T. E. Parker; T. P. Heavner; S. R. Jefferts; L. Hollberg; W. M. Itano; D. J. Wineland; J. C. Bergquist

doi:10.1103/physrevlett.90.150802

arXiv · physics/0212109

Testing the stability of fundamental constants with the 199Hg+ single-ion optical clock

S. Bize·S. A. Diddams·U. Tanaka·C. E. Tanner·W. H. Oskay·R. E. Drullinger·T. E. Parker·T. P. Heavner·S. R. Jefferts·L. Hollberg·W. M. Itano·D. J. Wineland·J. C. Bergquist

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Abstract

Over a two-year duration, we have compared the frequency of the 199Hg+ 5d106s 2S 1/2 (F=0)<-> 5d9 6s2 2D 5/2 (F=2) electric-quadrupole transition at 282 nm with the frequency of the ground-state hyperfine splitting in neutral 133Cs. These measurements show that any fractional time variation of the ratio nu(Cs)/nu(Hg) between the two frequencies is smaller than +/- 7 10^-15 / yr (1 sigma uncertainty). According to recent atomic structure calculations, this sets an upper limit to a possible fractional time variation of g(Cs) m_e / m_p alpha^6.0 at the same level.

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S. Bize, S. A. Diddams, U. Tanaka, C. E. Tanner, W. H. Oskay, R. E. Drullinger, T. E. Parker, T. P. Heavner, S. R. Jefferts, L. Hollberg, W. M. Itano, D. J. Wineland, J. C. Bergquist. 2002-12-31. Testing the stability of fundamental constants with the 199Hg+ single-ion optical clock. https://doi.org/10.1103/physrevlett.90.150802

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