Resonance measurements ofd−fandd−gintervals in lithium Rydberg states

Abstract

Using a laser-excitation, optical-detection scheme, we have observed microwave transitions from the $\mathrm{nd}$ to the $\mathrm{nf}$ and $\mathrm{ng}$ orbital levels in lithium states with principal quantum number $n$ from 7 to 11. These measurements yield precise values for the $d$, $f$, and $g$ state fine-structure intervals as well as $d-f$ and $d-g$ energy separations. Within the accuracy of these measurements, the fine structures are found to be hydrogenic. The dipole polarizability of the ${\mathrm{Li}}^{+}$ core is determined from the $d-f$ and $d-g$ energy splittings. The $d-f$ intervals are compared to pseudopotential calculations.