One- and two-photon spectroscopy of Cs Rydberg states with and without external E-fields

Sihong Gu, Shunsheng Gong, Bingmo Liu +3 more

Clinton Douglas Harper

Jianming Zhao, Jingxu Bai, Suying Bai +1 more

The ultralong-range Cs2 Rydberg molecules consisting of a Rydberg, nD5/2 ( principal quantum number n =35-38), and a ground state atom, 6S1/2 (F=4) are prepared by a two-photon photoassociation spectroscopy in an ultracold Cs gas. This kind of molecule is bound with the low energy scattering and has a permanent dipole moment. We observe two Rydberg-ground state molecular spectra, one is deep-bound molecule, TΣ state, bound by triplet s-wave scattering length and the other one is shallow-bound molecule, S,TΣ state, bound by mixed singlet-triplet s-wave scattering length. The binding energy of Rydberg-ground molecules are attained by analyzing the two photon photoassociation spectrum, corresponding permanent dipole moment is measured by applying an external electric field, which is compared to the calculation.

Claude Fabre, S. Haroche

Ting Gong, Zhonghua Ji, Jiaqi Du +3 more

We demonstrate measurement of the permanent electric dipole moment (EDM) of 85 Rb 133 Cs molecules in the absolute vibrational ground state by microwave (MW) coherent spectroscopy. The rotational states of the considered molecules, which are formed from short-range photoassociation of mixed cold atoms, are nondegenerated under external electric field. To measure the EDM based on electric-field-induced shifts of the sublevels of X 1 Σ + ( v = 0, J = 1) rotational state, we utilized a MW coherent spectroscopy, which has a higher resolution than depletion spectroscopy and one-photon MW spectroscopy and can also eliminate the influence from Stark shift of the excited state existing in both spectroscopies above. In order to acquire accurate electric intensity, electromagnetic induced transparency spectroscopy of 85 Rb Rydberg atoms is used to implement the calibration. The permanent EDM of 85 Rb 133 Cs molecules is finally determined to be 1.266(15) D, which agrees with the theoretical calculations and is comparable with the value of its isotopic molecule.

Д.Ф. Зарецкий, M. M. Yudkevich