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arXiv · 2110.00043

Measurement of the tune-out wavelength for $^{133}$Cs at $880$ nm

Apichayaporn Ratkata·Philip D. Gregory·Andrew D. Innes·Jonas A. Matthies·Lewis A. McArd·Jonathan M. Mortlock·M. S. Safronova·Sarah L. Bromley·Simon L. Cornish
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Abstract

We perform a measurement of the tune-out wavelength, $λ_{0}$, between the $D_{1}$, $6^2S_{1/2}\rightarrow6^2P_{1/2}$, and $D_{2}$, $6^2S_{1/2}\rightarrow6^2P_{3/2}$, transitions for $^{133}$Cs in the ground hyperfine state $(F=3, m_{F}=+3)$. At $λ_{0}$, the frequency-dependent scalar polarizability is zero leading to a zero scalar ac Stark shift. We measure the polarizability as a function of wavelength using Kapitza-Dirac scattering of a $^{133}$Cs Bose-Einstein condensate in a one-dimensional optical lattice, and determine the tune-out wavelength to be $λ_{0}=880.21790(40)_{\textrm{stat}}(8)_{\textrm{sys}}$ nm. From this measurement we determine the ratio of reduced matrix elements to be $\left|\left<{6P_{3/2}\| d\|6S_{1/2}}\right>\right|^{2}\left|\left<{6P_{1/2}\| d\|6S_{1/2}}\right>\right|^{2}=1.9808(2)$. This represents an improvement of a factor of 10 over previous results derived from excited-state lifetime measurements. We use the present measurement as a benchmark test of high-precision theory.

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Apichayaporn Ratkata, Philip D. Gregory, Andrew D. Innes, Jonas A. Matthies, Lewis A. McArd, Jonathan M. Mortlock, M. S. Safronova, Sarah L. Bromley, Simon L. Cornish. 2021-09-30. Measurement of the tune-out wavelength for $^{133}$Cs at $880$ nm. https://doi.org/10.1103/physreva.104.052813

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