Probing Ultracold Collisional Dynamics with Frequency-Chirped Pulses

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.

Accepted by PRA

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Cited by in corpus (6)

• Interatomic potentials, electric properties, and spectroscopy of the ground and excited states of the Rb_2 molecule: Ab initio calculations and effect of a non-resonant field
• Coherent Control of Ultracold Collisions with Chirped Light: Direction Matters
• Coherent control of ultracold 85Rb trap-loss collisions with nonlinearly frequency-chirped light
• Perspectives for coherent optical formation of strontium molecules in their electronic ground state
• Dynamics of interacting bosons in a double well potential-harmonic versus chirp modulation
• Stabilization and time resolved measurement of the frequency evolution of a modulated diode laser for chirped pulse generation