  The effects of mode-mode and isospin-isospin correlations on nonequilibrium
chiral dynamics are investigated by using the method of the time dependent
variational approach with squeezed states as trial states. Our numerical
simulations show that large domains of the disoriented chiral condensate (DCC)
are formed due to the combined effect of the mode-mode and isospin-isospin
correlations. Moreover, it is found that, when the mode-mode correlation is
included, the DCC domain formation is accompanied by the amplification of the
quantum fluctuation, which implies the squeezing of the state. However, neither
the DCC domain formation nor the amplification of the quantum fluctuation is
observed if only the isospin-isospin correlation is included. This suggests
that the mode-mode coupling plays a key role in the DCC domain formation.
