  Using the optical Stern-Gerlach model, we have recently shown that the
non-local correlations between the internal variables of two atoms that
successively interact with the field of an ideal cavity in proximity of a nodal
region are affected by the atomic translational dynamics. As a consequence,
there can be some difficulties in observing violation of the Bell's inequality
for the atomic internal variables. These difficulties persist even if the atoms
travel an antinodal region, except when the spatial wave packets are exactly
centered in an antinodal point.
