Determination of Quantum Defects and Core Polarisability of Atomic Caesium via Terahertz and Radio-Frequency Spectroscopy in Thermal Vapour [dataset]

We present new measurements of the quantum defects and core polarisabilities in caesium utilising measurements of transition frequencies between Rydberg states (14 ≤ n ≤ 38) of 133Cs using terahertz (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. Using these results, energies for nℓj Rydberg states can be estimated to a precision of a few MHz or less.