  We experimentally investigate the atom optics kicked particle at quantum
resonance using finite duration kicks. Even though the underlying process is
quantum interference it can be well described by an $\epsilon$-pseudoclassical
model. The $\epsilon$-pseudoclassical model agrees well with our experiments
for a wide range of parameters. We investigate the parameters yielding maximal
momentum transfer to the atoms and find that this occurs in the regime where
neither the short pulse approximation nor the Bragg condition is valid.
Nonetheless, the momentum transferred to the atoms can be predicted using a
simple scaling law, which provides a powerful tool for choosing optimal
experimental parameters. We demonstrate this in a measurement of the Talbot
time (from which $h/M$ can be deduced), in which we coherently split atomic
wave-functions into superpositions of momentum states that differ by 200 photon
recoils. Our work may provide a convenient way to implement large momentum
difference beam splitters in atom interferometers.
