title: Enhancement of Ultracold Molecule Formation Using Shaped Nanosecond Frequency Chirps.
abstract: We demonstrate that judicious shaping of a nanosecond-time-scale frequency chirp can dramatically enhance the formation rate of ultracold (87)Rb(2) molecules. Starting with ultracold (87)Rb atoms, we apply pulses of frequency-chirped light to first photoassociate the atoms into excited molecules and then, later in the chirp, deexcite these molecules into a high vibrational level of the lowest triplet state a (3)Σ(u)(+). The enhancing chirp shape passes through the absorption and stimulated emission transitions relatively slowly, thus increasing their adiabaticity, but jumps quickly between them to minimize the effects of spontaneous emission. Comparisons with quantum simulations for various chirp shapes support this enhancement mechanism.
authors.affiliation: Department of Physics, University of Connecticut, Storrs, Connecticut 06269, USA.
authors.forename: J L
authors.initials: JL
authors.lastname: Carini
authors.affiliation: Department of Physics and Optical Engineering, ORT Braude, P.O. Box 78, Karmiel, Israel.|Department of Physical Chemistry and the Fritz Haber Research Center for Molecular Dynamics, The Hebrew University, 91094 Jerusalem, Israel.
authors.forename: S
authors.initials: S
authors.lastname: Kallush
authors.affiliation: Department of Physical Chemistry and the Fritz Haber Research Center for Molecular Dynamics, The Hebrew University, 91094 Jerusalem, Israel.
authors.forename: R
authors.initials: R
authors.lastname: Kosloff
authors.affiliation: Department of Physics, University of Connecticut, Storrs, Connecticut 06269, USA.
authors.forename: P L
authors.initials: PL
authors.lastname: Gould