  Single atoms are interesting candidates for studying quantum optics and
quantum information processing. Recently, trapping and manipulation of single
atoms using tight optical dipole traps have generated considerable interest.
Here we report an experimental investigation of the dynamics of atoms in a
modified optical dipole trap with a backward propagating dipole trap beam,
where a change in the two-atom collision rate by six times has been achieved.
The theoretical model presented gives a prediction of high probabilities of
few-atom loading rates under proper experimental conditions. This work provides
an alternative approach to the control of the few-atom dynamics in a dipole
trap and the study of the collective quantum optical effects of a few atoms.
