High-density cooling of cesium atoms in the gravito-optical surface trap

Summary form only given. The gravito-optical surface trap (GOST) confines cesium atoms by a blue-detuned repulsive evanescent wave (EW) in combination with gravity. Horizontal confinement is provided by the conservative optical dipole potential of a hollow, cylindrical laser beam, far blue-detuned from resonance. For preparing a very cold and dense cesium gas in the GOST, we use evanescent wave ´Sisyphus´ cooling, which is based on inelastic reflections of the atoms from the EW. Using this method we have obtained a temperature of 3 /spl mu/K, which corresponds to an average distance of the atoms from the surface of 19 /spl mu/m. As a very important feature for attaining very high densities, EW cooling allows one to keep the atoms predominantly in the absolute ground state, thus avoiding trap loss by light assisted collisions.