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Atomic Clock with 1x10-18 Room-Temperature Blackbody Stark Uncertainty



Kyle P. Beloy, Nathan M. Hinkley, Nate B. Phillips, Jeffrey A. Sherman, Marco Schioppo, John H. Lehman, Ari D. Feldman, Leonard M. Hanssen, Christopher W. Oates, Andrew D. Ludlow


The Stark shift due to blackbody radiation (BBR) is a key factor limiting the performance of many atomic frequency standards, with the BBR environment inside the clock apparatus being difficult to characterize at a high level of precision. Here we demonstrate an in-vacuum radiation shield that furnishes a uniform, well-characterized BBR environment for the atoms in an ytterbium optical lattice clock. Operated at room temperature, this shield enables specification of the BBR environment to a corresponding fractional clock uncertainty contribution of 5.5x10-19. Combined with uncertainty in the atomic response, the total uncertainty of the BBR Stark shift is now 1x10-18. Further operation of the shield at elevated temperatures enables a direct measure of the BBR shift temperature dependence and demonstrates consistency between our evaluated BBR environment and the expected atomic response.
Physical Review Letters


BBR shift, blackbody radiation shift, optical lattice clock, Stark effect, ytterbium


Beloy, K. , Hinkley, N. , Phillips, N. , Sherman, J. , Schioppo, M. , Lehman, J. , Feldman, A. , Hanssen, L. , Oates, C. and Ludlow, A. (2014), Atomic Clock with 1x10<sup>-18</sup> Room-Temperature Blackbody Stark Uncertainty, Physical Review Letters, [online], (Accessed May 29, 2024)


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Created December 31, 2014, Updated February 19, 2017