Optimized production of a cesium Bose-Einstein condensate
  We report on the optimized production of a Bose-Einstein condensate of cesium atoms using an optical trapping approach. Based on an improved trap loading and evaporation scheme we obtain more than $10^5$ atoms in the condensed phase. To test the tunability of the interaction in the condensate we study the expansion of the condensate as a function of scattering length. We further excite strong oscillations of the trapped condensate by rapidly varying the interaction strength. 
Tobias Kraemer, Jens Herbig, Michael Mark, Tino Weber, Cheng Chin,   Hanns-Christoph Naegerl, Rudolf Grimm