Speaker
Description
The isotope shifts (IS) in the frequency of an atomic transition are approximately linearly correlated with the shifts in another transition. This linearity is reflected in the so-called King-plot analysis. It has been suggested to search for deviations from linearity as a way to probe beyond-Standard-Model interactions mediated by light bosons [1]. These searches require availability of precision IS data in a chain of isotopes of a given element. In a recent report on precision spectroscopy in a pair of Yb$^+$ transitions [2], a large nonlinearity was observed in the King-plot, that primarily arises due to the quadratic field shift [2], or the influence of the nuclear deformation on the field shift [3]. Further availability of precision IS data in the same element is crucial to check modeling of the cause of the nonlinearity [3], and potentially separate within Standard-Model effects from possible new physics contributions to the nonlinearity [4].
We will discuss an experiment involving precision spectroscopy of the $^1S_0-^1D_2$ optical transition in neutral Yb, in order to determine the IS in the naturally abundant, nuclear-spin zero Yb isotopes. We will present our preliminary experimental results, and show a joint King-plot of our data combined with those on Yb$^+$, that reveals an order of magnitude larger nonlinearity, compared to that of the Yb$^+$ work.
[1] J. C. Berengut, et al., Phys. Rev. Lett. 120,091801 (2018).
[2] I. Counts, J. Hur, D. P. L. Aude Craik, H. Jeon, C. Leung, J. C. Berengut, A. Geddes, A. Kawasaki, W. Jhe,and V. Vuletic, Phys. Rev. Lett. 125, 123002 (2020).
[3] Saleh O. Allehabi, V. A. Dzuba, V. V. Flambaum, and A. V. Afanasjev. Phys. Rev. A 103, L030801 (2021).
[4] J. C. Berengut, C. Delaunay, A. Geddes, and Y. Soreq, Phys. Rev. Research 2, 043444 (2020)
