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 105 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.Comment: 9 pages, 7 figures, submitted to Appl. Phys.