Precise measurements of polarizabilities of cesium nS Rydberg states in an ultra-cold atomic ensemble

Abstract

We present precise measurements of polarizabilities of cesium n S _1/2 ( n = 65–75) Rydberg states by Stark spectroscopies. In experiment, Rydberg atoms are excited via a two-photon scheme of a standard magneto-optical trap and detected by the field ionization technique. The Stark shift is measured by analysing the spectroscopy under an external electric field. The polarizability, α , is acquired by fitting the experimental data of Stark shifts with ${\Delta}W=-\frac{1}{2}\alpha {E}^{2}$ . The theoretical model is applied to numerically simulate the Stark map and corresponding level shifts, related deviation between the experimental measurements and calculations are less than 2%. The scaling law of polarizabilities, $A\cdot {\left({n}^{{\ast}}\right)}^{7}+B\cdot {\left({n}^{{\ast}}\right)}^{6}$ ( n * is effective principal quantum number), is attained, that shows a good agreement with the measurements.

Keywords

• ultra-cold Rydberg atom
• polarizability
• Stark spectra