  Dynamical evolution of quantum mechanical squeezing and entanglement in a
two-mode Bose-Einstein condensate (TBEC) with an adiabatic, time-varying Raman
coupling is studied by finding analytical expressions for these quantities. In
particular, we study the entanglement between the atoms in the condensate as
well as that between the two modes. The nature of the enhanced quantum
correlations in TBEC is clarified by considering squeezing and entanglement
both with and without the nonlinear interaction turned on; it is found that
entanglement approaching maximal value can be achieved with the nonlinear
interactions present. Somewhat counter-intuitively, greater squeezing is found
in the absence of nonlinear interactions. This is due to the collapses and
revivals of the TBEC quantum state induced by the nonlinear interactions. In
addition, results involving the self-trapping phase state of TBEC indicate
potential for creating a dynamically stable, macroscopic entangled quantum
state which is relatively robust with respect to atom number fluctuations.
