Determination of quantum defects and core polarizability of atomic cesium via terahertz and radio-frequency spectroscopy in thermal vapor

Abstract

We present new measurements of quantum defects and core polarizabilities in cesium (Cs133), based on transition frequency measurements between Rydberg states (14≤n≤38) obtained through THz and radio-frequency spectroscopy in a thermal atomic vapor. We perform a global fitting of our measurements to extract quantum defects of the s1/2, p1/2, p3/2, d3/2, d5/2, f5/2, f7/2, g7/2, and g9/2 electronic states. Transitions between high angular momentum states (4≤ℓ≤8) were measured to extract the Cs+ dipole and quadrupole polarizabilities. We find αd=15.729(18)a03 and αq=76.3(1.9)a05 respectively. Using these results, and accounting for the covariances between parameters in the global fit, the energies for nℓj Rydberg states can be estimated to a precision of a few MHz or less.