Electric dipole matrix elements for the $6p{}^2{P}_J\to 7s{}^2{S}_{1/2}$ transition in atomic cesium

Abstract

We report a measurement of the ratio of electric dipole transition matrix elements of cesium for the $6p{}^2{P}_{1/2}\to 7s{}^2{S}_{1/2}$ and $6p{}^2{P}_{3/2}\to 7s{}^2{S}_{1/2}$ transitions. We determine this ratio of matrix elements through comparisons of two-color, two-photon excitation rates of the $7s{}^2{S}_{1/2}$ state using laser beams with polarizations parallel to one another vs.\ perpendicular to one another. Our result of $R\equiv ⟨7s{}^2{S}_{1/2}||r||6p{}^2{P}_{3/2}⟩/⟨7s{}^2{S}_{1/2}||r||6p{}^2{P}_{1/2}⟩=1.5272(17)$ is in excellent agreement with a theoretical prediction of $R=1.5270(27)$. Moreover, the accuracy of the experimental ratio is sufficiently high to differentiate between various theoretical approaches. To our knowledge, there are no prior experimental measurements of $R$. Combined with our recent determination of the lifetime of the $7s{}^2{S}_{1/2}$ state, we determine reduced matrix elements for these two transitions, $⟨7s{}^2{S}_{1/2}||r||6p{}^2{P}_{3/2}⟩=-6.489(5)a_0$ and $⟨7s{}^2{S}_{1/2}||r||6p{}^2{P}_{1/2}⟩=-4.249(4)a_0$. These matrix elements are also in excellent agreement with theoretical calculations. These measurements improve knowledge of Cs properties needed for parity violation studies and provide benchmarks for tests of high-precision theory.

10 pages, 4 figures

References in corpus (5)

• Systematic evaluation of an atomic clock at 2e-18 total uncertainty
• Spectroscopic observation of SU(N)-symmetric interactions in Sr orbital magnetism
• QED shifts in multivalent heavy ions
• Precision lifetime measurement of the cesium $6P_{3/2}$ level using ultrafast pump-probe laser pulses
• Magic wavelengths for the $5s-18s$ transition in rubidium

Cited by in corpus (1)

• Measurement of the radial matrix elements for the $6s^2{S}_{1/2}\to 7p^2{P}_J$ transitions in cesium