SC 99-12 Peter Backhaus, Burkhard Schmidt, Marcos Dantus: Control of photoassociation yield: A quantum-dynamical study
of the mercury system to explore the role of pulse duration
from nanoseconds to femtoseconds Appeared in: Chemical Physics Letters 306 (1999) pp.18-24
Abstract: The photoassociation process shows strong dependence on
the temporal
duration of the electromagnetic field pulses and their
frequencies. This
dependence is investigated using quantum mechanical
simulations that
include all ranges of impact parameters and contributions
from
bound-to-bound transitions. The photoassociation yield of
mercury atoms to
produce excimer dimers is enhanced for short (ps) and for
ultrashort (fs)
pulse durations. Ultrashort laser pulses effectively
overlap the entire
range of free-to-bound transition, therefore achieving a
maximum
probability. Short pulses show a maximum in the
photoassociation yield when
their carrier frequency overlaps a particular
free-to-bound spectroscopic
resonance. Implications of these calculations on efforts
to control
bimolecular reactions are discussed.
Keywords: photoassociation,
laser pulse control
PACS: 32.80.Qk, 34.10.+x, 34.50.Gb, 34.50.Rk