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Probing Ultracold Collisional Dynamics with Frequency-Chirped Pulses

M. J. Wright·J. A. Pechkis·J. L. Carini·P. L. Gould
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Abstract

We report on the dynamics of ultracold collisions induced by near-resonant frequency-chirped light. A series of identical chirped pulses, separated by a variable delay, is applied to an ultracold sample of 85Rb, and the rate of inelastic trap-loss collisions is measured. For small detunings of the chirped light below the atomic resonance, we observe that the rate of collisions induced by a given pulse can be increased by the presence of an earlier pulse. We attribute this to the enhancement of short-range collisional flux by the long-range excitation of atom pairs to an attractive molecular potential. For larger detunings and short delays, we find that a leading pulse can suppress the rate of collisions caused by a following pulse. This is due to a depletion of short-range atom pairs by the earlier pulse. Comparison of our data to classical Monte-Carlo simulations of the collisions yields reasonable agreement.

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M. J. Wright, J. A. Pechkis, J. L. Carini, P. L. Gould. 2006-11-01. Probing Ultracold Collisional Dynamics with Frequency-Chirped Pulses. https://doi.org/10.1103/physreva.74.063402

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