  We study a string of neutral atoms with nearest neighbor interaction in a 1D
beam splitter configuration, where the longitudinal motion is controlled by a
moving optical lattice potential. The dynamics of the atoms crossing the beam
splitter maps to a 1D spin model with controllable time dependent parameters,
which allows the creation of maximally entangled states of atoms by crossing a
quantum phase transition. Furthermore, we show that this system realizes
protected quantum memory, and we discuss the implementation of one- and
two-qubit gates in this setup.
