arXiv:2410.09520 · Physical Review A
Measurements of the hyperfine structure of n P J Rydberg states by microwave spectroscopy in Cs atoms
Rong Song, Jingxu Bai, Zhenhua Li, Yuechun Jiao, Suotang Jia, Jianming Zhao
Abstract
We present measurements of the hyperfine structure (HFS) of the $n{P}_{J}$ Rydberg states for a large range of principal quantum number $n$ $(n=41--55)$ employing microwave spectroscopy in an ultracold cesium Rydberg ensemble. A microwave field with $30\text{\ensuremath{-}}\textmu{}\mathrm{s}$ duration couples the $nS\ensuremath{\rightarrow}nP$ transition, yielding a narrow linewidth spectroscopy that approaches the Fourier limit, which allows us to resolve the hyperfine structure of $n{P}_{J}$ states. By analyzing the hyperfine splittings of $n{P}_{J}$ states, we determine the magnetic dipole HFS coupling constant ${\overline{A}}_{\mathrm{HFS},{P}_{1/2}}=3.760(26)$ GHz for the ${P}_{1/2}$ state, and ${\overline{A}}_{\mathrm{HFS},{P}_{3/2}}=0.718(27)$ GHz and ${\overline{B}}_{\mathrm{HFS},{P}_{3/2}}=\ensuremath{-}0.084(102)$ GHz for the ${P}_{3/2}$ state. Systematic uncertainties caused by stray electromagnetic field, microwave field power, and Rydberg interaction are analyzed. This measurement is significant for the investigation of Rydberg electrometry and quantum simulation with dipole interaction involving the $n{P}_{J}$ state.