  We systematically investigate the mergers of neutron star-white dwarf
binaries from beginning to end, with focus on the properties of the inflows and
outflows in accretion disks and their electromagnetic emissions. Using
population synthesis models, we determine a subset of these binaries in which
the white dwarf companion undergoes unstable mass transfer and complete tidal
disruption, forming a large accretion disk around the neutron star. The
material evolves according to an advection-dominated accretion disk model with
nuclear burning, neutrino-emissions, and disk-surface wind ejection. The
extreme dynamics of the entire process has proven difficult for analytic
analysis, and thus currently the properties are poorly understood. The outflows
from the mergers are iron- and nickel-rich, giving rise to optical and infrared
emissions powered from the decay of the radioactive iron-type isotopes,
calculated via the SuperNu light-curve code. We find these systems capable of
powering bright, yet short-lived, optical transients with the potential to
power gamma-ray bursts.
