OPTICAL-PUMPING WITH LASER-INDUCED-FLUORESCENCE

We describe a new procedure for optical pumping that is based on laser-induced fluorescence (LIF). The procedure is demonstrated by optically exciting a sample of Rb-85 atoms, which then creates a population imbalance between the ground state hyperfine levels of Rb-87 by ''LIF depopulation pumping''. Though optical pumping with this technique increases the intensity dependent light-shift coefficient (i.e., ac Stark shift) of the Rb-87 0-0 hyperfine transition, it reduces the frequency dependent light-shift coefficient by at least an order of magnitude. Since the stabilization of the diode laser wavelength is a significant challenge in the development of laser-pumped gas-cell atomic clocks, it is anticipated that optical pumping with LIF will be of benefit to atomic clock technology.