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Figure 1: a) Typical classical trajectory of an atomic collision showing the flux enhancement effect. The solid (dashed) line indicates the atom's trajectory while in the excited (ground) state.The incoming atom approaches from the right. The atom pair is excited at by the trap laser pulse and is accelerated by the attractive long-range potential. After spontaneous decay, it proceeds to , where it may be excited again by a probe laser pulse. The atom pair is then accelerated quickly into short range, where either RE or may occur, leading to trap loss. b) Molecular potential diagram for the same process.

  
Figure 2: Classical simulations of time-resolved collisions at K. The trap (probe) laser intensity and detuning are 15.2mW/cm (7W/cm ) and , respectively. The five curves are generated using the C coefficients and excited-state lifetimes for each of the Hund's case (c) attractive molecular states. Plotted is the probability for flux enhancement to take place as a function of collision time (i.e., time to travel from to .)

  

Figure: 3 (a) Timing of the trap and probe laser pulses for the experiment. The trap laser is on at low (3.8mW/cm ) intensity for 5 s. This is followed by a series of short (100ns), intense (15.2mW/cm ) trap pulses. The probe pulses are 100ns long and are peaked at time after the peak of each trap pulse. The entire pattern repeats every s. (b) plotted as a function of . The flux enhancement effect increases only after a delay of 200ns, indicating a minimum collision time of . It then drops off slowly, in reasonable agreement with the simulations (Figure 2.)