Recent applications and advances in laser manipulation of atoms

A series of experiments which owe their existence to advances in laser cooling and trapping of atoms will be presented. Emphasis will be given to the demonstration of an interferometer for atoms using laser cooled sodium atoms and the mechanical effects of velocity sensitive stimulated Raman transitions. This interferometer, configured as an accelerometer, was used to measure the acceleration due to gravity of an atom with a resolution of 3 parts in 108, and interference was observed for atomic wavepackets separated by as much as 6 mm. Other applications of stimulated Raman transitions will be discussed: These transitions have been used to prepare ensembles of atoms with one- dimensional velocity spreads as narrow as 270 μm/sec, to measure the temperature of polarization gradient cooled atoms, and recently, they have been used in conjunction with optical pumping pulses to cool an ensemble of sodium atoms to a temperature of 100 nK in one-dimension (more than an order of magnitude below the single photon recoil temperature). Laser cooling and trapping techniques were employed to create an open-quotes atomic fountainclose quotes source for the interferometer experiment. In the fountain geometry, cold atoms launched on vertical ballistic trajectories turn due to gravity within the confines of the apparatus. Application of this source to rf spectroscopy of the sodium groundstate hyperfine interval and to observation of the Casimir/van der Waals force between sodium atoms and a dielectric surface will be reviewed