Semi-Classical Calculations of Ultracold Collisions with Frequency-Chirped Light: Dependence on Chirp Rate

We conduct semi-classical monte-carlo simulations of ultracold collisions utilizing frequency-chirped laser light on the nanosecond timescale. Previous work revealed partial control of light-assisted collisional mechanisms with relatively slow chirp rates (10 GHz/$\mu$s). Collisions induced with positive chirped light enhance the inelastic collisional loss rate of atoms from a magneto-optical trap whereas these trap loss collisions can be blocked when negative chirped light is used. Early quantum and classical simulations show that for negative chirps the laser's frequency continually interacts with the atom-pair during the collision. We investigate how this process depends on the chirp rate and show that by moderately speeding up the chirp ($>$ 50 GHz/$\mu$s), we can significantly enhance the difference in the collisional loss rate induced by the negative and positive chirps, gaining nearly full control of the collision.